A posture analysis app in your browser: what it measures and what it can't
TrackMyPosture is a posture app that runs in your browser and uses your webcam. There is nothing to install and nothing to wear. This page covers what it measures, where it falls short and what it costs, so you can decide if it is the right kind of tool before you sign up.
If you would rather try it than read about it, the free posture check takes 30 seconds and needs no account.
What it measures
In every frame, a pose model called MoveNet places points on your nose, eyes, ears and shoulders. It runs in your browser. From those points the app works out:
- Shoulder angle: how far the line between your shoulders is from level, in degrees. Within 3° counts as level.
- Shoulder symmetry: the height difference between your shoulders, compared with how wide apart they are.
- Head direction: whether your head is turned left or right, or angled up or down, from where your nose sits compared with your ears.
The analyse screen from our test setup, with a stock photo played through a fake camera. The blur on the face is privacy mode, which is on by default.
How the score works
The score is made of three parts:
- 50% shoulder symmetry
- 30% shoulder angle: full marks within 3°, none at 13° or more
- 20% how sure the model is that it sees each shoulder
Head direction is not part of the score. It shows up in the one fact printed under the score instead. The photo above shows why that matters: the head is clearly turned, the score is still 96%, and the fact says "Your head was turned to your left most of the time."
When we tilted the same picture by 7°, the score fell to 70% and the fact changed to "Your right shoulder sat about 9° higher than your left." That also shows a limit: the app can't tell tilted shoulders from a tilted laptop, so face the camera straight on.
What it can't see
The camera sees you from the front. It can't see the curve of your back, and leaning in towards your screen with level shoulders may not change the score at all. A high score means your shoulders were level and clearly visible. It does not mean that you sit well.
We have tested it in Chrome on a computer. We have not yet confirmed it on Safari, Firefox or a phone.
It is a measuring tool, not a treatment, and research has not settled whether posture causes back pain. If something hurts, talk to a doctor or physiotherapist.
What gets saved
The video stays on your device. About once a minute, your account saves one row of numbers: the angles, scores and directions above. The statistics page charts those rows, and a weekly email sums them up. Deleting your account deletes them.
The statistics page on a test account with sample data.
What it costs
The free plan includes 45 minutes of tracking a month. When they run out, tracking stops until the next month and your statistics stay. That is enough to find out whether the app suits you, but not to run it through a working day.
Pro removes the limit for $6.99 a month or $39 a year. The measurements are the same on both plans, and you can cancel at any time. See the pricing page for details.
The app can also make a sound when your shoulders tilt, if you want a reminder as well as the numbers.