Tennis has entered a new era of precision.
From professional tournaments to club matches, smart technology now helps players, coaches, and umpires make confident decisions and gain deeper insights into performance.
Line-calling and smart net post systems are leading this shift toward accuracy and data-driven play.
Below is a full overview of the best systems available in 2025 and how each one works.
What Is a Tennis Line-Calling System?
A line-calling system, also known as an electronic line-calling system, uses cameras, sensors, and AI software to determine whether a ball lands in or out.
The technology tracks the ball’s flight, calculates its trajectory, and produces real-time results.
Many systems also record video, generate statistics, and provide training data that help players analyze their game.
1. Baseline Vision
Origin: Europe
ITF Approved | Portable Device
Discount Code: LEO1
Baseline Vision leads the new wave of portable, AI-based line-calling devices.
Designed for convenience and precision, it brings professional accuracy to club and recreational players without complicated installation.
The system includes two high-definition cameras, LED panels, and speakers on both sides of the unit, all connected to a dedicated mobile app.
Core Components
- Two Full HD cameras (60 fps) capturing both sides of the court
- LED indicators and audio cues for line calls
- Built-in AI processor that analyzes live video in real time
- Detachable battery, LAN and USB ports, and carrying case
- Mobile app for line calls, video replays, and player statistics
Key Features
Baseline Vision delivers automatic line calls, performance tracking, and video replays through its AI engine.
The Baseline app also includes fun and competitive modes like Deeper and 2-Minute Challenge, where players can test shot depth or consistency.
The unit sets up in minutes and automatically tracks every point and rally.
Players can then review data such as shot placement, ball speed, and footwork inside the app.
Summary:
Baseline Vision is compact, precise, and ideal for anyone who wants professional-grade line-calling with accessible pricing. It combines simplicity, smart features, and reliable accuracy in one portable device.
2. Hawk-Eye
Origin: United Kingdom
Used by: ATP, WTA, and Grand Slams
Hawk-Eye is the original leader in computer vision for tennis. It uses ten high-speed cameras positioned around the court to track the ball’s movement. Each camera captures the ball from a different angle, and the system triangulates these frames to calculate the ball’s exact path.
This process produces the “Shot Spot,” the familiar replay used in professional tournaments to confirm line calls. Results appear almost instantly and are used by umpires, broadcasters, and players.
Summary:
Hawk-Eye remains the benchmark for reliability and precision at the highest level. It is built for professional competition and not designed for general club use.
3. Zenniz
Origin: Finland
Availability: USA and Europe
ITF Approved
Zenniz offers one of the most complete smart-court systems available. It includes a smart net post with integrated cameras, microphones, LED displays, and a touchscreen interface. It also features a baseline camera, mobile app, and online dashboard for coaches and tournament organizers.
Key Features
- Dual Tracking Technology combining visual and audio detection
- Automatic in/out display on the net post screen
- Player statistics covering movement, rally depth, and shot speed
- Video highlights and live streaming
- Interactive training drills with instant feedback
How It Works
Zenniz uses 30 microphones positioned around the court to capture impact sounds and player movement. Four synchronized cameras then track the ball’s visual flight path. By merging these two data streams, the system builds a complete digital model of the court for precise calls and advanced analytics.
Summary:
Zenniz blends accurate line-calling with coaching and training features. It is practical for both competitive play and personal practice sessions, offering high value for clubs and players who want more than just line calls.
4. FoxTenn
Origin: Spain
Professional Use
FoxTenn takes a different approach from other systems. Instead of predicting where the ball landed, it records the exact frame of contact when the ball hits the court. The system uses more than 40 high-speed cameras synchronized with laser scanners, capturing up to 2,500 frames per second.
Measurements
- Ball and player speed
- Bounce position and height
- Ball trajectory and angle
- Player hitting zones
This combination of optical and laser technology allows FoxTenn to deliver unmatched accuracy, even in challenging conditions such as low light or fast surfaces. It is the system of choice for many professional tournaments and broadcast productions.
Summary:
FoxTenn focuses on absolute accuracy rather than estimation. It is designed for the professional circuit and is not aimed at recreational players.
5. Wingfield
Origin: Germany
ITF Approved
Wingfield turns any traditional court into a smart court with its Wingfield Box, a replacement for one net post that houses two high-speed cameras. An additional baseline camera can be added for a TV-style perspective.
Its AI system, known as Walter, recognizes players and tennis balls from the video feed and continues to improve its accuracy through self-learning.
Key Features
- AI-based ball and player tracking
- Automatic video recording for matches and training
- Easy setup that requires only power and an internet connection
- Integration with national ranking systems in Germany
- Mobile app with smart filters and match statistics
Wingfield gives players access to their recordings and detailed analysis directly through its app. Clubs can use the data for official match validation and player development.
Summary:
A flexible and intelligent net post system that brings certified match tracking and professional analytics to any court.
6. In/Out
Origin: USA
Portable and Affordable
In/Out is a small, wireless line-calling solution designed for everyday players. It consists of two sensors: one attached to the net post and another placed near the baseline. The system connects to a mobile app and provides immediate line calls and replays.
Highlights
- Automatic line calls with high precision
- Built-in touchscreen for reviewing shots
- One to two hours of battery life
- Cloud-based AI coaching and statistics
- Data export options in CSV and JSON formats
- Optional training drills and match streaming
How It Works
The sensors detect court lines and ball impacts, creating a virtual map of the playing area. Players can review footage on the device itself or in the app after play.
Summary:
In/Out offers accurate line calls and essential match data at an affordable price. It is ideal for players who want a lightweight and portable option that works anywhere.
Final Thoughts
Line-calling and smart-court systems have moved from the professional stage to everyday courts around the world. Hawk-Eye and FoxTenn continue to define accuracy at the elite level. Zenniz, Wingfield, and Baseline Vision bring those capabilities to clubs and training environments, while In/Out provides a practical, portable option for casual players.
Among these, Baseline Vision stands out in 2025 for its balance of precision, portability, and accessibility. It gives players a professional-grade experience without the complexity or cost of larger systems.
Smart technology is now a part of tennis at every level. Whether you compete on the tour, train at your local club, or just want a fair call on match night, there is now a solution that fits your game.
