One-Fix Swing
Film one tennis swing. Get the one thing to fix first, and a drill for it. No app, no account, and your video never leaves your phone.
Get One-Fix on your home screenOpens full-screen and works on court, even with a weak signal.
1 · Choose your stroke
2 · Film one swing
- From the sideStand side-on to the camera, like a TV side view.
- 3–4 m awayYour whole body in frame, head to feet.
- One strokeA clip of 3–8 seconds with one full swing.
- Steady phoneProp it on a bag or ask a friend to hold it.
3 · Your one fix
All checks
How it works, and its limits
Your clip is analysed in your browser with Google's MediaPipe pose model, which finds 33 body points in each frame. The tool finds contact from the fastest movement of your hitting hand (or its highest point on a serve) and checks a few fundamentals around it: contact in front, shoulder turn, knee bend, finish and head stillness for groundstrokes; arm extension, leg drive, contact height and head position for the serve. You get the first failing check, in order of what usually matters most.
It can't see the ball, the racquet face, spin or where the shot lands, and the targets are general guidelines rather than a coach's eye. This is an early prototype: use it as a second opinion, not a verdict.
Privacy: the video stays on your device. The page only downloads the pose model from Google; no frames or results are uploaded. Your last result is remembered in this browser so you can see progress next time.
Built by Keith Chiu with AI-assisted development. Runs entirely in your browser.