Let me show you the best AI detectors on the market.
I’ve tested every single one of these tools to save your time and money.
Top Picks
Here are the top picks for the busy readers:
👉 1. Aidetector.com
👉 2. Originality AI
👉 3. Winston AI
Disclaimer: This article is reader-supported. If you choose to pay for the tools listed in this article, I might earn a small commission at no cost to you.
Now, let me show you my reviews and results with every single one of these tools.
(Update: I made a similar post earlier this year. However, based on emails I got, I updated this one with the latest attempts. I also removed some older tools and updated the post to be even clearer. Hope you like it!)
How I Tested Them
Two years ago, I tested AI detection tools, and they were awful.
They often flagged human-written text as AI and AI-written text as human.
Even the better tools were easy to trick — one typo could change a score from 100% AI to 0%. Not great.
This year, I decided to run the same experiment again.
I test each AI detector with:
- 3 AI-generated texts
- 3 human-written texts
If a detector passes those, I then try tweaking the AI-written text to see if it can be made to look human.
You’ll find the prompts and full details for this experiment at the end of the post.
1. Aidetector.com
aidetector.com is my favorite AI detector partner out there.
This tool detects not only text but also images.
Needless to say, this tool is ridiculously easy to use.
Just copy-paste text to the AI detector view and wait 2 seconds for the score. (The same goes for the AI images.)
Let me show you my results.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 2/3 correct, which is decent.
This brings me up to an important point: AI detection is possible but not 100% accurate, so make sure to only use it for general direction, not absolute truth.
Here are the AI detection scores for the 3 AI-written posts:
That’s 3/3 correct.
These samples are indeed fully AI-written.
Results with Images
Then, I tried the image detector feature.
Here are the two real images I used this tool on:
The AI got both correct! That’s impressive.
Here are the two AI-generated images I tried with this model:
Awesome! The AI got both of these right, too, despite them being generated with the newest OpenAI o4 model.
Noteworthy
This is the best overall AI detector I tested. It works for both text and images, and it’s still simple to use.
The paid plan gives the best results, though.
It was also tough to fool. When I added typos to AI-written samples, it didn’t fall for it.
That said, no tool is perfect, and your results may vary.
If you plan to use these tools to “catch students cheating,” don’t bother.
Even the best detectors can wrongly flag formally human-written content as fully AI-generated.
Other Features
Along with detecting AI-written text and images, Aidetector.com lets you run batch analysis to scan multiple documents at once.
It gives detailed probability scores showing how confident it is in each prediction, which helps with borderline cases.
There’s also API access if you want to add detection to your own apps or workflows.
You can download reports to keep records or share results easily.
2. Originality AI
Originality AI is the most popular AI detector tool out there.
This tool doesn’t just detect AI from text, but it also helps you check for plagiarism and even do content optimization. The latter is the part I love about this tool a lot. It’s fast and shows very new results, as long as it finds those on the internet.
But let’s focus on the AI detection this time.
My Results
Let me show you my experience with the AI detection features of Originality AI.
#1 AI Content Detector
To run AI detection on text, select the AI check box on the left.
Copy-paste the text to this view.
Hit “Scan”.
Here’s what I got on my AI-written sample:
That’s a 100% AI-written score, which is correct. The post was indeed produced by AI.
Let’s try it a couple of times to see how well it does.
AI text sample 1:
Correct!
AI text sample 2:
Correct!
AI sample 3:
That’s 3/3 correct.
Let’s see if it also correctly identifies human-written text as human-written and not AI…
Human text sample 1:
Correct!
Human text sample 2:
It missed that one. It suggests that the whole thing is written by AI, even though it’s me.
But here, I have to give it the benefit of the doubt because the text chapter is so short. The shorter it is, the harder it is to say.
Let’s try with a longer sample.
Human text sample 3:
Correct!
Let’s do one more. This time, I added a blog post, which is almost 1,000 words in length, that I wrote by hand.
That’s 3/4 correct.
The longer the post, the better I find this tool to be based on my tests. That’s why there’s a 100-word minimum word limit in Originality.ai.
Epic!
The AI can clearly see patterns and structures in content that are not that easy to see.
#2 Plagiarism Check
Originality does plagiarism checks, too. Just select the “Plagiarism check” feature and copy-paste content into the text field.
I copied and pasted a text chapter from my blog post to view to check the score:
Originality gives it an 80% match.
This means it’s plagiarized, which is true because that post already exists online (and I’m stealing it from myself, essentially).
But after I took that post, rewrote it with ChatGPT, I’m no longer getting a plagiarism alert.
This is correct because now the wording makes it an original piece of content.
Still, even with 100% original content, you might see some “plagiarism.”
For example, if your text says “I drank milk yesterday,” it’s possible someone else has written the same thing before.
To better understand the content and any possible plagiarism, check the sources where the text might have been taken from:
If you click one of those matches, it points you to the sections from which the content has been taken.
Noteworthy
Originality is not just an AI detector.
It’s an AI-powered content optimization platform that shows cool metrics, statistics, and does competitive analysis too.
Make sure to test all the other features in the AI scan view to make the most out of it.
Other Features
Originality AI isn’t just for detecting AI-generated text — it’s a complete content quality platform.
It offers plagiarism checks, fact verification, readability scoring, and grammar correction in one place.
Recent updates added bulk scanning for site-wide audits, browser extensions for Chrome and WordPress, and API access so you can build checks into your workflow.
It also has content optimization and paraphrase detection in multiple languages.
It’s more advanced than the simple detectors, but if you’re serious about publishing with integrity, it’s a strong choice.
3. Winston AI
The next epic AI detector tool on the list is Winston AI.
It can check blog posts, GPT outputs, images, and plagiarism. Here’s what worked, what didn’t, and what to know before using it.
Let me show you how it works and my results.
👉 Try Winston AI Detector Free
My Results
Winston is easy to use. Just sign up and open up the app.
After signing up, you’ll see a view that looks like this:
This is where you can choose between text detection and image detection.
1. Text Content Scan
Winston AI lets you scan any text block and shows you how likely it is to be AI-generated.
Pick “Start content scan” in the app dashboard.
Add text into this view:
Hit “Scan text”.
In just seconds, you will see a score page like this:
It gives you a human score between 0 and 100%.
0 means it’s entirely AI-generated, and 100% means it’s entirely human-written.
It also shows what parts of the text are AI-generated. It’ll also give you a readability score, but I’ll talk about that a bit later.
I tested Winston AI to see how well it works. I took some samples of my blog posts that I’ve written by hand and this is what I got:
That’s epic. It got them all right.
Then, I tested the AI text samples. Here’s the first one that I created with ChatGPT:
This is the score:
Epic! It suggests that’s 1% human-written, which means it’s AI-written, which is exactly what it is.
Let’s try another one:
Here’s the score:
Once again, it gave a near-zero human-written score for the content piece because I used AI to create it.
Let’s do one more:
The score was 1% human, which means the tool nailed it again.
Don’t forget to check the specific sections that Winston believes are AI-written by scrolling down the report.
You can even hover your mouse over the text sections to see what score that chapter gets.
Just remember that no AI detector is perfect.
Sometimes AI models change, and the patterns change too. This makes AI hard to detect until the tools catch up with it.
Also, formal writing can be hard to distinguish from AI-written text.
Lastly, the shorter the text, the harder it is to tell if it’s AI or human.
👉 Try Winston AI Detector Free
2. Readability Score
Let’s do the readability score scan next.
This happens from the bottom sliders in the text editor (where you can also check for plagiarism):
I took this example blog post and copied and pasted it into the view.
Here’s a score that I got for it:
I also got a list of suggestions to make the content more readable.
To accept the content fixes, click “Correct” in the top corner of each fix.
This swaps out the red crossed-out text with the blue suggestions.
Of course, readability is just one part of a good blog post.
The most important thing for bloggers and SEOs is to share unique information — something others haven’t covered.
Without that, your content won’t rank.
But once that’s done, improving readability can help take your content to the next level and tick all the boxes.
👉 Try Winston AI Detector Free
3. The AI Image Scan
Let’s move on to the AI image scan feature.
You can upload images, and Winston AI will try to tell if they were generated by tools like Midjourney or DALL·E.
It doesn’t just look at resolution or metadata — it scans for visual patterns common in AI-generated visuals.
For example, here the AI told me that my image is 95% human, which it indeed is (as it’s a real photograph).
That gave it almost a 100% human score, which is indeed what this is.
Lastly, don’t forget to check the integrations. These allow you to connect Winston AI with your favorite apps.
For example, if you use Winston with Chrome, you can install the extension to make it work on any page.
Isn’t that handy?
👉 Try Winston AI Detector Free
Other Features
Along with spotting AI-generated text, Winston AI has a solid set of tools for serious users.
It combines AI detection with plagiarism checks, an AI image and deepfake detector, and built-in writing feedback like readability scoring.
You can upload documents, URLs, or even images using OCR.
It also highlights suspicious sentences with an AI prediction map and lets you download or share PDF reports.
The platform supports multiple languages, has a Chrome extension, team accounts, and an enterprise API for developers.
👉 Try Winston AI Detector Free
4. QuillBot
QuillBot is an AI writing tool for paraphrasing, grammar checking, and summarizing. But this tool also has one of the best free AI detectors on the market.
Let’s see what kinds of results I can get with it.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 3/3 correct!
Here are the AI detection scores for the 3 AI-written posts:
Clean sweep! That’s also 3/3 correctly identified as AI-written.
Noteworthy
The AI detector is free to use, but after 5 tries it asks you to create an account before you can keep going.
Since it did so well in my tests, I tried to fool it by adding typos and mistakes.
But guess what? It still got it right:
This AI-written piece with some human-like typos did not fool the detector at all.
Other Features
QuillBot is an AI writing assistant platform.
Along with detecting AI-generated content (including categories like “AI-generated” and “AI-refined”), it offers a paraphraser, grammar and spelling checker, summarizer, translator, citation generator, and plagiarism scanner in over 100 languages.
It supports bulk uploads and works with Chrome, Word, and desktop apps. There’s also a Synonym Slider to adjust tone.
While the AI detector wasn’t the strongest I tested, the other tools — like the AI grammar checker — are worth a look.
5. Merlin
Merlin is an AI content platform that offers a free AI detector that spots AI in your writing.
Let’s see how it plays out when it comes to the AI detection.
My Results
First, here are the human-written samples:
That’s 3/3 correct.
It’s a great start. I test these tools in a completely random order, and I don’t think I’ve seen a start this good in hours.
Let’s try it with the AI samples:
That’s technically 3/3 correct.
But also, 2 out of the 3 samples just gave a 60% AI score. So it’s 50:50 with a lot of content, which still makes it too unreliable to use.
NoteWorthy
I ran into some UI issues. When I tried detecting AI, the tool got stuck. Refreshing the page fixed it.
I like that you can use it without signing up, and the dark theme is a nice touch.
That said, even with a small test, it’s clear this tool isn’t 100% foolproof for AI detection.
Other Features
Merlin is a browser-based AI assistant that comes with an AI detector and many other tools.
You can use it to chat with web pages, PDFs, videos, and documents through an extension.
It can summarize content, translate, rewrite, help with research, and even generate images.
You can create and manage projects with instructions, upload different file types, and share resources with your team.
It works on desktop, browser, and mobile, and supports popular AI models like GPT-4, Claude, Gemini, Mistral, and more.
6. Phras.ly
Phras.ly seems promising. They claim their detector is 99.8% accurate. Better yet, it’s 100% free to use.
But let me show you my results with the AI detector.
My Results
First, here are the human-written samples:
That’s 3/3 correct.
There’s one catch — this tool uses other AI detectors to create its results. In a way, it’s averaging what the other tools on this list say. So it’s not really its own AI detector.
Still, if it works, what’s not to like?
Let’s try it with the AI samples:
That’s 1/3 fully correct.
If you count the fact that it gave over 50% AI score for all the samples, then that’s a full 3/3, right?
That’s decent. But it’s not 99.8% right as it suggests.
NoteWorthy
This tool uses many AI detectors behind the scenes.
You can see that in the score. It’s not their AI detector but a combination of other tools on this list.
Other Features
Phras.ly goes beyond basic AI detection with a full AI writing enhancement toolkit.
It pairs its text detector (claimed 99.8% accuracy) with a built-in paraphraser, or “humanizer,” that can rewrite at easy, medium, or aggressive levels to reduce AI fingerprints.
It also has a plagiarism checker, bulk upload support, API access, and a sentence-selection feature so you can pick the version that best matches your voice.
Phras.ly is privacy-focused — your content isn’t stored — and reports are simple to download or share.
7. Scribbr
Scribbr is a proofreading and editing service that helps you improve your writing.
It offers plagiarism checks, citation tools, and expert feedback on grammar, clarity, and structure.
Let’s see if its AI detector is as good as it claims.
My Results
Here are the AI detection scores for the 3 human-written posts:
Yay! That’s 3/3 of tests correctly identified as human-written.
Here are the AI detection scores for the 3 AI-written posts:
Awesome! That’s also 3/3 of tests correctly identified as AI-written.
Noteworthy
This AI passed all my tests. It didn’t just say the AI-written pieces were “partly AI-written” — it correctly marked them as 100% AI-written, exactly as they were.
So I had to try a trick that worked two years ago: adding a typo to see if I could fool the detector.
Here’s what happened:
It still flagged the text as AI-written, even with the typo I added.
That’s impressive — it’s definitely getting harder to fool these tools.
One thing to note: you can’t use the Scribbr AI detector with less than 80 words of text.
Other than that, I think this free tool is just awesome.
Other Features
Scribbr isn’t just for AI detection — it’s part of a full academic writing system.
It has a plagiarism checker that searches a large database of web pages and scholarly publications.
You also get grammar and citation tools, an AI proofreader, and paragraph-level feedback on AI-generated content in multiple languages. The platform focuses on privacy — your work isn’t stored — and you can download or share detailed reports.
That said, the AI detector itself didn’t leave a great impression.
8. CopyLeaks
CopyLeaks AI Detector spots AI-generated text by analyzing patterns and writing style.
It’s designed for educators, businesses, and content creators to check for AI-written content.
Let’s see how well it works.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 3/3 correct!
Here are the AI detection scores for the 3 AI-written posts:
That’s 3/3 correct, too.
Noteworthy
I remember this tool being good even two years ago. I’m not sure if it was my number one pick, but I know it was in the top five AI detectors I tested back then.
The only issue it had this time was with the first AI-written sample, which it marked as 91% AI-written.
Now, let’s see if we can fool it with some typos. I removed a couple of periods and added a few typos to this text:
The AI detector was still able to point out that the content was fully written by AI.
That’s epic! So no longer do those simple tricks work on these best tools.
Other Features
CopyLeaks isn’t just an AI detector — it’s a full content integrity platform.
Along with spotting AI-generated text from ChatGPT, Gemini, Claude, and others with over 99% accuracy, it has a plagiarism checker that searches academic databases and billions of web pages.
You can adjust sensitivity to catch paraphrased or spun content, scan source code for AI-generated snippets, and check for licensing issues. It also works with LMS and API integrations, so you can add checks to Google Docs, learning platforms, or your own app.
9. NoteGPT
NoteGPT is an AI tool that lets you quickly summarize, transcribe, and organize different types of content, including YouTube videos, PDFs, lectures, audio files, and images.
One of its features is an AI detector, which I’m testing today. The best part is it’s free, and you don’t need to sign up to use it.
Let’s see the results.
My Results
Here are the AI detection scores for the human-written samples:
That’s 3/3 correct!
Here are the AI detection scores for the 3 AI-written posts:
That’s 1/3 correct if you want a 100% score.
But to be fair, the AI flagged all of them to be over 50% AI-written, so in that sense, I can call it 3/3 too.
However, it wasn’t as confident as other tools on the list.
Noteworthy
NoteGPT is not just an AI detector but more like an AI quick tools platform.
Besides AI detection, this platform can summarize, transcribe, and organize all kinds of content, including YouTube videos, PDFs, lectures, audio, and images.
You can paste a video link or upload a document, and it will instantly give you a clean transcript, a short summary, and even flashcards or mind maps to download.
It’s free to start, but after a few uses, you’ll need to create an account.
That’s worth noting because some companies try to offer every feature under the sun, and while each one works okay, none of them are perfect. This is why I suggest using a platform that focuses on AI detection instead of trying to do 100 different things.
Other Features
NoteGPT is more than just an AI detector — it’s more like a note-taking and study tool.
You can summarize YouTube videos, PDFs, articles, audio files, and more, then organize your insights in folders or mind map layouts.
It also has an AI Humanizer that finds AI-generated text and rewrites it to sound more natural.
You can use it without logging in, and browser extensions are on the way, making it easy to fit into your daily writing workflow.
That said, the detection system didn’t leave a good impression. It simply doesn’t work.
10. ZeroGPT
ZeroGPT is a free AI text detection tool that identifies whether text is AI-generated or human-written.
Let me show you my results with it.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 3/3 correctly identified as “human-written.”
Here are the AI detection scores for the 3 AI-written posts:
That’s 3/3 somewhat correctly identified AI-written pieces of text.
Verdict
This tool is simple to use — no signup needed, and the analysis takes just a second.
It’s free and fast.
In my tests, it correctly marked all three of my human-written pieces as “human-written.”
However, one AI-written text got a 20% AI score, even though it was fully AI-generated. So it’s not something to rely on completely.
Still, I’m surprised at how much better these detectors are compared to two years ago when I last tested them.
Other Features
Like many tools on this list, ZeroGPT isn’t just an AI checker — it’s a full set of writing tools in one platform.
It includes grammar correction, summarizing, paraphrasing, translation, a word counter, and even an AI chat feature to help refine your content.
You can use it through a browser extension, upload files in bulk, or connect it with an API.
11. SurgeGraph.io
SurgeGraph is an SEO tool that also has a free AI detector.
I tested it, and it’s convenient because you don’t need to sign up. Just go to the site, paste your text into the box, and wait about three seconds.
Here are my results.
My Results
First, here are the human-written samples:
That’s 3/3 correct.
With the very first sample, it showed 11% AI, which wasn’t correct. So right away, it’s questionable how well it works.
Here are the tests with the AI-written text samples:
That’s just 1/3 correct.
So, once again, a tool that works well with human-written samples but can’t detect AI.
NoteWorthy
SurgeGraph isn’t really an AI detector — it’s an SEO tool that happens to have a free AI checker.
Because of that, it’s not surprising that the detector doesn’t work well. It got the human-written posts right but failed badly on the AI samples.
This isn’t new. Any AI detector that isn’t updated with the latest AI patterns won’t work well. This one is mainly there to promote SurgeGraph’s main SEO tools, so it’s hard to say when it was last updated.
Other Features
SurgeGraph.io offers tools for SEO and content editing.
It has a long-form text generator that focuses on keyword use, a keyword research tool to find search terms, and an editor that gives on-page suggestions.
You also get topic grouping to organize ideas and a simple planner to track articles. All of these are meant to help you write original content that’s easier to optimize for search engines.
The AI detector, though… it just doesn’t work.
12. Grammarly
Grammarly is an AI writing assistant that checks grammar, spelling, punctuation, and style.
It gives suggestions to improve clarity and readability, making it useful for emails, essays, and professional documents. As a content creator, I use Grammarly daily for spell-checks and similar tasks — it’s great at them.
But today, I’m testing its AI detection feature (which I didn’t even know it had).
Let’s see how it does.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 3/3 correctly identified as “human written.”
Terrific!
Here are the AI detection scores for the 3 AI-written posts:
Technically, that’s 0/3 correct.
That’s not so good. Yes, it was able to tell that there was some “AIness” in the writing in every AI content piece.
However, it wasn’t flagging these entirely AI-written pieces of text as AI-written.
Noteworthy
Grammarly’s AI detector is slower than most of the others.
While other tools gave results in one or two seconds, Grammarly took almost 10 seconds to analyze my short text samples — and longer texts will take even more time.
So as an AI detector, it’s a bit of a letdown compared to the rest. But I have to say, Grammarly’s AI writing features are excellent, and I’ve been using them for over four years.
Other Features
I use Grammarly every day and have for almost five years — but not for AI detection. I use it for grammar checking.
Grammarly offers grammar and spelling checks, clarity improvements, and tone adjustments. It can rephrase sentences, suggest better word choices, and give readability scores.
It also has plagiarism detection that checks against online sources. You can use it as a web app, a browser extension, or through integrations with Word and Google Docs. I especially like the Chrome extension.
The AI detector, though, just doesn’t work.
13. GPTZero
GPTZero is an AI tool made to detect text generated by models like GPT.
It looks at writing patterns to decide whether the content is human-written or AI-generated.
Let’s see how it does in my tests.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 3 out of 3 correct again.
However, it didn’t mark them as 100% human-written — the scores were around 95% or 98% — so it’s not perfect with the human-written tests.
Here are the AI detection scores for the three AI-written posts:
That’s 2/3 correct. Also, it only flagged one of the AI-written content pieces as 100% AI. So in this sense, it just got 1 right completely.
Noteworthy
This tool wasn’t very accurate with my samples. It only gave a 100% score for a fully human-written text once — the rest always had some doubt.
On the plus side, it’s fast and lets you check up to 50,000 characters of text at a time.
Other Features
This tool mainly focuses on AI detection, and it’s a bit strange that they didn’t make a better tool that would be higher on the list.
All the other AI-detection-only tools have worked so much better.
14. Isgen
Isgen is another AI detector platform that promises to spot any AI in any piece of writing.
Let’s see if it actually works.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 3/3 correct.
Promising start!
Here are the AI detection scores for the 3 AI-written posts:
That’s 1/3 correct.
Noteworthy
Most of the AI-written text was wrongly marked as human-written.
It also has some limits — it won’t accept text under 600 characters (about 100 words) and only allows up to 5,000 characters per check.
It didn’t perform as well as I expected, but it still got a few things right.
Other Features
Isgen can detect AI-generated and AI-edited images and identify the AI model used, along with a probability score.
It can also flag AI text at the sentence and phrase level, lets you upload multiple files at once, and allows you to export detailed reports.
The platform supports over 80 languages, offers bulk scanning, tracks document history, and includes a plagiarism checker and citation generator for academic work.
15. Undetectable AI
Undetectable AI is Forbes’ top-rated AI detection platform, claiming it can reliably tell AI-written text from human-written content.
Let’s see how it does. I’ve got high hopes after seeing that Forbes listing.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s just 2/3 correct.
This is actually one of the few tools on the list that failed with human-written text.
Here are the AI detection scores for the three AI-written posts:
That’s just 1/3 correct.
Noteworthy
So far, this is the worst-performing AI detector I’ve tested.
I’m honestly surprised Forbes lists it as the number one AI detector — it’s not.
I’m also not a fan of the UI. It looks like something thrown together over a weekend, right after ChatGPT launched.
I wouldn’t recommend this one.
Other Features
Undetectable AI combines an AI detector with a text humanizer that rewrites AI-generated content to make it harder to detect (which is a bit funny. I’ll talk more about that later in the post).
It lets you upload text, runs it through multiple detectors, and then edits sentence structures, word choices, and phrasing.
You can export reports, process large blocks of content at once, and track your documents from a dashboard. It’s free up to a certain limit, after which you’ll need a paid plan.
16. Surfer SEO
Surfer SEO is an AI content optimization tool designed to boost search rankings.
It analyzes top-ranking pages and gives data-driven suggestions for keywords, structure, and readability.
It also has an AI detector — let’s see if it’s as good as they claim.
My Results
Here are the AI detection scores for the 3 human-written posts:
That’s 3/3 correct.
The only small blemish is the fact that it said one of the text pieces was 1% AI-written. But we’ll let that slide.
Here are the AI detection scores for the 3 AI-written posts:
That’s 0/3 correct — a complete failure with AI-written text.
Noteworthy
This told me every text piece was human-written, even though half of the time it was AI-generated.
So it’s fair to say this AI detector doesn’t work.
Also, it didn’t accept inputs with fewer than 100 words, so I had to extend the sample number 2 in the human-written text chapters.
Other Features
Surfer SEO includes tools to support on-page SEO and content planning beyond AI detection.
If you’ve read my blog content, I don’t really use SEO tools like this. Also, because this is a tool that didn’t work in the AI detection side, I would stay away from it.
Nonetheless, I still want to share what it does for the curious readers.
Its Content Editor scans content and gives you keyword and structure guidance, while a built-in plagiarism checker highlights duplicates in your draft.
Surfer gives you file version history, image insertion, and table formatting features.
The platform includes a standalone Audit tool that evaluates existing pages for SEO issues — like missing terms, internal links, or structure improvements — and a Keyword Research module that identifies search volume, difficulty, and content clusters.
17. SciSpace
SciSpace is an AI tool that helps you find, read, and understand research papers without getting lost in complicated jargon.
You can upload any PDF or pick from millions of papers, then ask questions, get summaries, and see everything explained in plain language.
It also has an AI detector that checks if the text is original or AI-written.
I tested it myself. Let me show you how it went.
My Results
First, here are the human-written samples:
That’s technically 3/3 correct.
However, with the last two samples, it suggested about 30% AI, which is not true. So it already kind of failed the challenge.
Here are the tests with the AI-written text chapters:
That’s technically 0/3 correct.
Yes, it was 50/50 with two samples. But that’s a coin flip, and you can’t draw any conclusions from that. You’d either want to see this score being 0% or 100% or very close to either.
NoteWorthy
If you try it, make sure to check the “Scientific” or “Non-Scientific” checkboxes based on what your text is. It can swing the score by a large margin if the AI thinks this is not supposed to be scientific text, but it is.
This tool lets you try the AI detector once without signing up. Then you need to sign up, and after 5 attempts, it will prompt you to buy a plan. However, the detector still seems to work if you just ignore the payment window.
Notice that this tool is not just an AI detector but rather a scientific paper helper platform with all sorts of features.
But for whatever that’s worth, this tool didn’t work. It already stumbled with the human-written samples, and it completely failed with the AI ones.
Other Features
SciSpace lets you check PDFs or pasted text for AI-generated writing, scoring with sentence-level breakdowns, and report downloads.
It includes a chat assistant for understanding and summarizing research papers, a paraphrasing tool with multiple tones, and an in-text citation generator.
You can search across tons of academic papers, pull data from PDFs, and export citations in different styles.
It also supports organization with folders and keeps a history of your scans and documents.
18. Smodin
Smodin is another free AI detector platform that mainly focuses on AI content and AI detection.
Let’s see what kinds of results I got with it.
My Results
First, here are the human-written samples:
That’s 3/3 correct.
It’s a promising start.
Let’s test it with the AI samples to see more results:
That’s just 1/3 correct.
So this tool doesn’t work reliably enough to spot AI in your writing. It’s as simple as that.
NoteWorthy
The free use is limited on this AI detector. You can only check the AI 5 times per week for free, which to me is ridiculous, considering it’s advertised as a free AI detector.
It even has an IP tracking system to make sure you don’t use it for free for more.
Definitely not worth a shot.
Other Features
Smodin’s AI detector can flag AI‑written sections at the sentence level and supports uploads of text or documents up to 5,000 characters.
It highlights flagged sentences, offers a report download, and doesn’t require an account.
Beyond detection, it includes a plagiarism checker, paragraph rewriter, summarizer, citation tool, grammar corrector, translator, and an “AI humanizer” that rewrites AI-generated content.
It supports many languages and can process multiple files or bulk scans.
19. DeCopy AI
DeCopy AI is an AI platform.
I’m just going to call it that because there’s a tool for everything…
However, as you’ll soon see, the fact that a tool “does it all” usually means it doesn’t do anything at all.
Let me show you my results with the AI detector.
My Results
First, here are the human-written samples:
That’s technically 3/3 correct.
However, with all the content pieces, it says there’s between 15–30% AI in the mix, which is not true. So in this sense, it’s all wrong already.
Here are the tests with the AI-written text chapters:
That’s 0/3 correct.
This tool just doesn’t work. You get all these cool numbers and probability analysis, etc. But the truth is that it’s just not there. It claimed all my AI samples to be mostly human-written.
But then, it also claimed that my human-written posts are partially generated with AI.
NoteWorthy
Once again, this is a general-purpose AI platform that claims to have all the AI tools for everything.
But as it turned out, even the AI detector didn’t work at all, and it was the only tool I tested on this website. I think this just goes to show you that most AI detectors don’t work and that you should only use tools that focus on AI detection instead of trying to nail 100 things at the same time.
Other Features
DeCopy AI combines AI detection with tools that help refine text. You can summarize documents, simplify complex writing, humanize AI-generated content, and paraphrase sentences.
It also checks grammar and translates text into different languages.
On top of that, it supports uploading PDFs and large files, offers a Chrome extension, and lets you download detection reports.
It aims to be a utility for turning rough drafts into clearer, more natural content.
The AI detection system does not work, though.
20 Writer.com
Writer.com is an AI writing platform that offers a free AI detector. You can use it without signing up.
Let’s see how it plays out.
My Results
First, here are the human-written samples:
That’s 3/3 correct.
It looks promising. Even though it’s not a full 100% score in any of the results, it’s pretty close.
Let’s test it with the AI samples too:
That’s 0/3 correct.
Well, that’s embarrassing. This seems to be just another AI detector that’s stuck in time. The tool always gives you a human score closer to 100% — whether your content is written by AI or not… Interesting, to say the least.
NoteWorthy
I wish this worked. The platform looks cool, and it’s easy to use. The tool is fast, and the other features look promising as well. But as you can see, this just didn’t do it.
I thought this was an AI SEO/writing platform, but it appears that they’re now an AI agent platform.
I’ll come back to it a year or two from now, and let’s see if they’ve picked up on the latest trend then. 😉
Nonetheless, I don’t recommend using this detector. It just doesn’t work.
Other Features
Writer.com includes a simple AI detector for up to 5,000 words without a sign-up.
It also gives you a writing assistant with grammar and style suggestions, customizable style guides, and terminology management for teams.
There’s plagiarism detection, backlink checking, and a content editor that integrates SEO guidance, too. I have to be honest and say that I don’t use tools like this.
The platform supports team workflows with shared word quotas and API access for developers.
There’s real-time feedback through browser extensions and integrations with tools like Google Docs and Word.
The AI detector was one of the worst ones I’ve tested, though. It was easy to use, but it just didn’t work.
21. ContentDetector AI
ContentDetector AI is, as the name suggests, an AI-powered content detection tool that spots AI in your writing for free. This tool works without you signing up for it, which is nice.
But does it work? Let’s see how it plays out!
My Results
First, here are the human-written samples:
That’s technically 2/3 correct.
However, it wasn’t sure with any one of the samples, which already shows that the tool doesn’t really work.
Let’s test it with the AI samples to see more:
That’s technically 0/3 correct.
This failed miserably. This is one of the worst AI detectors I’ve tested. I mean, how do they even call it one? It gave better human scores for the text samples than the human-written ones did. So this tool claims AI writes better than humans? Makes no sense to me!
NoteWorthy
ContentDetector AI simply doesn’t work. I don’t recommend giving it a shot.
The UI is nice, and the tool doesn’t nag about paying/signing up. But that’s literally all there’s to it. The technology just doesn’t work, as simple as that.
Other Features
ContentDetector.ai scans pasted or uploaded text to flag AI-generated content and provides a percentage-based likelihood score.
It also includes a built-in word counter and supports unlimited free checks.
You can do bulk scans of multiple URLs or text blocks, run plagiarism and grammar checks, and assess readability.
Results are highlighted inline and can be downloaded as reports.
A browser extension and API integration allow for checks directly within workflows.
22. JustDone
JustDone is a comprehensive AI writer tool that helps users create authentic, polished content.
It offers AI Detector, Plagiarism Checker, Humanizer, Fact Checker, and Citation Generator to detect AI-generated or plagiarized text, and more
But let’s see how it plays out when it comes to the AI detection.
My Results
First, here are the human-written samples:
That’s 0/3 correct.
It’s just terrible. I mean, does it even do anything? Does it just want me to click that “Remove AI Content” button and pay a fortune for it to rephrase a harmless, good-looking human-written piece of text?
What a shame!
Let’s test it with the AI samples out of curiosity:
That’s technically 3/3 correct.
But did anything change? When I input human-written text, it gave me very similar AI scores.
In this sense, I’d say it failed all 6 tests miserably.
NoteWorthy
Don’t use. It doesn’t work. Not even close.
However, notice that the average AI score was lower with my AI-written text than with the human-written text. This was just pathetic. One of the worst ones I’ve ever seen, for sure.
Other Features
JustDone combines AI detection with text editing tools.
It can highlight AI‑sounding passages and then rewrite them in your style with a single click. It also checks facts, flags possible plagiarism, and offers grammar correction, paraphrasing, summarizing, quiz-generation, and citation tools.
You can access these features via uploads, browser extension, or API for developers.
You can export reports, run bulk scans (including code and PowerPoint), and bookmark document history, so it doubles as both a detector and a lightweight writing assistant.
My Test Setup
Let me show you how I tested these tools so that you can save time if you want to run a similar small-scale experiment.
I tested every single tool with the same inputs, that is:
- 3 human-written pieces of text
- 3 AI-written pieces of text
So it’s a very basic test to essentially rule out those that don’t work at all.
If you want to run a similar experiment but don’t want to spend time writing text (or generating it with AI), here are the prompts I used for the AI detectors.
Human-written sample 1
However, there’s another strategy you can use to earn much more with just a handful of subscribers. I’m talking about affiliate marketing. I started to post on my new channel about 10 months ago, and now I have 1,890 subscribers. That doesn’t sound like a lot, but that channel makes over $5,000 per month already. Last month was closer to $10,000. It all comes from affiliate marketing. So I test products and get paid whenever someone views my video and buys a product that I recommend. Also, because the products I test are all AI software, I can test those for free. So I’m making $5,000+ per month by sharing my screen and publishing it on YouTube. I just made a full 24-minute video on this topic and how you can do the same.
Human-written sample 2
Let me show you the best digital business card platforms and how to use them. These tools let you create a shareable business card in 60 seconds. With these tools, you can also manage contacts, and make sure your information is always up to date. You can even see analytics of how many people have viewed and interacted with your cards to see how you business card campaigns and networking strategies have played out. You can just say goodbye to the age-old paper cards that used to be the thing back in the day. Let me show you how it works and how to make the most out of it.
Human-written sample 3
To find success as a blogger, you need to solve problems for your audience. But not just any problems. Solve problems that nobody else has solved yet. In other words, be the first to the party. If you look at any successful blogs or bloggers, those have been around for decades. That’s like any other business. It’s not just hard work but it’s all about timing. For example, to start a successful crypto blog, you should’ve started one about 10 years ago. Or to start a successful weight-loss blog, you should’ve started 20 years ago. Once again, 99% of my blogging income is from trendy topics that have no coverage yet. That’s just the name of the game. If you target the wrong topic (which 99% of the topics are), it doesn’t matter if you use AI or not. You’re not going to find success either way.
AI-written sample 1
You don’t need a ton of subscribers to make money on YouTube. With affiliate marketing, even small channels can earn commissions. Here’s how: Pick a profitable niche where people are ready to buy, like tech, software, tools, or fitness gear. Join high-paying affiliate programs — skip low-commission links and go for SaaS tools, software, and recurring commission programs like SEMrush or TubeBuddy. Create buyer-focused content such as reviews, comparisons, and tutorials. People searching for “Best X for Y” or “How to Use X” are primed to buy. Optimize for search by using keywords in your title, description, and tags to rank on YouTube. Leverage other platforms by embedding videos in blog posts and sharing them on socials for extra traffic. With the right strategy, you can make money without a massive following.
AI-written sample 2
Traditional paper business cards are outdated. In today’s digital world, you need a smarter way to share your contact details. Digital business cards make networking effortless — letting you share links, social profiles, and contact info instantly with just a tap or a scan. But with so many platforms available, which one is the best for your needs? Whether you’re a freelancer, entrepreneur, or corporate professional, choosing the right digital business card platform can help you make a lasting impression. In this post, I’ll break down the best digital business card platforms, comparing features, pricing, and ease of use so you can find the perfect fit. Let’s dive in!
AI-written sample 3
Most bloggers struggle because they focus on topics that have already been covered a thousand times. If you want real success, don’t just write about popular subjects — solve problems that nobody else has solved yet. Think about your audience. What questions do they have that don’t have clear answers? What frustrations do they face that others overlook? Your job as a blogger is to fill those gaps. When you create content that delivers unique solutions, you stand out, rank higher on search engines, and attract a loyal following. Instead of writing another generic “10 Tips for Productivity” post, dig deeper. Find a niche issue, offer an original perspective, or explain something better than anyone else. That’s how you build authority and grow your blog into a real business. Success in blogging isn’t about writing more — it’s about solving the right problems.
Feel free to use these text samples.
Also, if you get good scores, don’t forget to tweak the AI inputs a bit by introducing intentional typos or mistakes. 2 years ago, that was enough to completely fool the AI detectors.
Yes, that’s a low sample size, but this already shows you if the tools can be trusted or not in the first place. Most tools fails with the first or second sample already, so you don’t need a big sample size to know that they do NOT work.
How to Do It Better
One thing you should keep in mind is that this test is limited.
I’m just testing the tools with some ChatGPT-written content as well as some samples that I’ve taken from my own blog posts.
If you want to get more reliable results, you have to do a whole bunch more experiments than with just one human and one AI model. Instead, you should:
- Use different prompts
- Use different LLMs, such as DeepSeek or Grok, to generate
- Choose text from multiple humans
- Try mixing AI into the human-written content
That’s a good couple of weeks of testing easily.
But to save you from that, I can tell you one thing: AI detectors are getting better. However, they will never be able to tell for certain if a text is AI-written or not. Thus, you shouldn’t judge people by these “AI scores.” It just doesn’t work.
The point of this post was to give you direction on what tools work decently and save you from having to sign up for / test all these services.
Also, if a couple of tests show bad signs, it’s not going to get better with more tests, so that’s also one of the reasons why I wrote this review — to test which tools are not working at all.
Hope you like it!
