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AI form checker

Not sure your squats are deep enough, or whether your hips sag in push-ups? Prop up your phone and train. This free AI form checker watches every rep, tells you out loud the moment something slips and scores your form after each set, for 28 exercises.

Check your formFree · no app, no sign-up · your video stays on your device

How to use it

Open the coach and press Start training. Allow the camera when your browser asks.
Prop your phone 2 to 3 metres away with your whole body in view: side-on for depth, back angle and hips, or facing it for knees and arms. For floor exercises, put it on the floor to your side.
Get into your start position and hold still for a second.
Train as usual. The coach recognises the exercise and calls out what to fix as it happens. After the set you see your clean reps, your form score and the one thing to work on next time.

How the AI checks your form

A body-tracking model (Google’s MediaPipe Pose) finds 33 points on your body about 30 times a second, right on your phone. From those points, the coach measures the angles that matter for your exercise: how deep you squat, whether your knees cave in, whether your hips sag in a plank, how far you lower in a push-up. It compares every rep with good form for that exercise, and when a fault lasts more than a moment, it tells you with a short spoken cue, the way a coach standing next to you would.

Read how AI form tracking works for the details, from camera frames to spoken cues.

What you get after each set

Clean reps: how many of your reps had no major fault.
A form score for the set, saved to your history so you can watch it improve.
The one thing to work on next time: the fault that cost you the most.

Which camera view?

Side-on shows depth, back angle and body line: best for squats, push-ups, planks, lunges and Romanian deadlifts.
Facing the camera shows your knees and both arms: best for knees caving in, uneven presses, curls and jumping jacks.
Each exercise guide says which view the coach prefers, and the coach tells you if it can’t see what it needs.

What it can’t do

It’s one phone camera, so joints hidden behind your body are estimated, and poor light or baggy clothes make it less accurate. Use it as a guide, not a judge. It gives general fitness feedback, not medical advice: if something hurts, stop and see a professional. And it only checks form on the 28 exercises it knows; anything else gets its reps counted.

Every check, exercise by exercise

Squat: Knees caving in, Back rounding, Chest dropping, Heels lifting, Shifting to one side, Above parallel, Too shallow, Not standing tall, Dropping too fast.
Lunge: Leaning forward, Knee caving in, Too shallow, Could go deeper, Rushing.
Romanian Deadlift: Back rounding, Squatting it, Hips not going back, Not hinging far enough, Short range, Not finishing tall, Lowering too fast.
Jump Squat: Knees caving in, Chest dropping, Too shallow, Not quite deep enough.
Side Lunge: Chest dropping, Too shallow, Not quite low enough, Not returning to the middle.
Glute Bridge: Back arching, Hips not high enough, Short at the top, Dropping too fast.
Calf Raise: Knees bending, Not high enough, Short at the top, Dropping too fast.
Wall Sit: Hips too high, Leaning forward.
Push-up: Hips sagging, Hips too high, Head dropping, Too shallow, Not quite low enough, Not locking out, Dropping too fast.
Knee Push-up: Hips sagging, Hips too high, Head dropping, Too shallow, Not quite low enough, Not locking out, Dropping too fast.
Bicep Curl: Elbows drifting, Swinging, Half rep, Short at the top, Not extending fully, Dropping the weight.
Shoulder Press: Leaning back, Uneven arms, Soft lockout, Partial press.
Lateral Raise: Arms too high, Swinging, Arms not high enough, A little short, Dropping the weights.
Front Raise: Arms too high, Leaning back, Arms not high enough, A little short, Dropping the weights.
Bent-over Row: Standing up, Short pull, Not quite all the way, Arms not straightening, Dropping the weight.
Overhead Tricep Extension: Elbows flaring out, Elbows drifting forward, Not lowering far enough, Short range, Not straightening.
Tricep Dip: Drifting away from the bench, Too shallow, Not quite low enough, Not locking out.
Pull-up: Swinging, Chin not over the bar, Not quite to the bar, Not hanging fully.
Plank: Hips sagging, Hips too high, Head dropping.
Side Plank: Hips dropping.
Crunch: Pulling on your neck, Not curling up enough, A little short.
Sit-up: Not sitting up, Not quite upright, Dropping back down.
Lying Leg Raise: Knees bending, Legs not high enough, A little short, Dropping your legs.
Mountain Climbers: Hips sagging, Knee not driving in, Short drive.
Jumping Jacks: Feet not wide, Arms not overhead, Arms a bit low.
High Knees: Knees not high enough, Knees a bit low.
Butt Kicks: Heels not high enough, Kicks a bit low.
Burpee: Not reaching the plank, Plank not flat.

Questions and answers

Can AI really check my exercise form?

For the basics, yes: depth, range of motion, knees caving in, hips sagging, back rounding, swinging and tempo can all be measured from a camera. It can't feel what you feel, so think of it as a second pair of eyes, not a replacement for a coach or a physiotherapist.

Which exercises does it check?

All 28 exercises it recognises, including squats, lunges, Romanian deadlifts, push-ups, curls, shoulder presses, rows, pull-ups, planks, sit-ups, jumping jacks and burpees. Every check is listed on this page.

Do I need to wear anything special?

No markers or sensors. Fitted clothes help the camera see your joints, and good light from the front or above helps too.

Is my video uploaded?

No. The tracking runs on your device: your video is never uploaded, recorded or stored, and you don't need an account.

Ready? Prop up your phone.

It's the same free AI coach for every exercise: it recognises what you're doing, counts out loud and tells you when your form slips.