AI body fat calculator
Calculate body fat % with AI
Upload a clear full-body photo and get a visual estimate in seconds. Repeat the same check-in monthly to track changes—photos are processed in memory, not stored.
- Full body visible, head to ankles
- Arms relaxed at your sides
- Even front lighting, no hard shadows
- Fitted clothing and a neutral pose
First successful estimate free · No card or account required
1
photo to get started
0
photos stored by FormCheck
1×
recommended every 4 weeks
How it works
One private photo. An honest range. A repeatable baseline.
01
Capture consistently
Use one front-facing, full-body photo in neutral lighting and a relaxed pose.
02
Review the range
The model checks photo quality first, then returns a range and confidence—not false precision.
03
Repeat in four weeks
Recreate the setup and compare your private numeric results to see the direction.
Reliable photo checklist
Make the next photo comparable.
- — Head-to-ankles framing
- — Arms relaxed at your sides
- — Even front lighting
- — Fitted athletic clothing
- — Camera level at waist height
- — No flexing or post-workout pump
Photo examples
What a usable check-in photo looks like.
Good · full bodyHead to ankles visible, fitted clothing, neutral front pose.
Photo: SoyBreno on Unsplash
Good · relaxed stanceArms at your sides, even lighting, consistent distance.
Photo: Shoham Avisrur on Unsplash
Avoid · croppedTorso-only crops hide proportions and often get rejected.
Photo: UnsplashBuilt for consistency
A useful trend beats a confident guess.
Daily weight moves with water, food, and timing. FormCheck helps you reproduce the same photo setup, records an honest estimate range, and compares like with like.
Example result
18%
Estimated range 16–21% · medium confidence
Your actual result includes capture feedback and a repeatable next check-in date.
The progress problem
You do not need another perfect number. You need to know if the work is working.
Your first successful estimate is free. Subscribe only when you want repeat check-ins, comparisons, and private trend reports.
Two prices. Same progress.
Your first successful estimate is free. Both plans unlock the same full tracking access—up to 5 check-ins every month.
Monthly
$7/month
Flexible billing. Same full tracking access—cancel anytime, billed monthly.
Annual · Best value
$49/year
Best value (~$4.08/mo). Same full tracking access—billed once a year, save 42%.
Privacy by design
Your photo is input, not a permanent record.
FormCheck removes image metadata, sends the photo securely for the analysis request, and does not store the source image. Only your numeric result and analysis details are saved to your private account.
Read the privacy details →Questions, answered honestly.
Is this a medical body-fat measurement?
No. It is a directional visual estimate. It should not replace DEXA, clinical advice, or decisions about your health.
What kind of photo works best?
Use a recent front view with your full body visible from head to ankles, arms relaxed, fitted clothing, a neutral pose, and even front lighting.
Can I use a smartphone photo?
Yes. Keep the phone level at about waist height, avoid wide-angle distortion, and stand far enough away to include your full body.
How do lighting and clothing affect the result?
Hard shadows can exaggerate definition and loose clothing can hide body shape. Even lighting and fitted athletic clothing make repeat comparisons more useful.
How accurate is the estimate?
Photo-based estimates have meaningful uncertainty and vary with pose, lighting, clothing, camera angle, and individual body-fat distribution. FormCheck reports a range and confidence instead of claiming clinical precision.
Are my photos stored?
FormCheck processes photos in memory for the request and does not save the source images. Your numeric result is saved to your private account.
What does the free estimate include?
Your first successful estimate includes a body-fat range, confidence, general model observations, capture feedback, and a suggested next check-in date. No card or account is required.
How quickly will I get a result?
Most usable photos are analyzed in seconds. Large uploads or a slow connection can take longer.
How often should I check in?
Every four weeks is usually enough to see a useful direction. Repeat the same lighting, clothing, pose, distance, and time of day.
Can I compare this with DEXA, scales, or tape methods?
Yes, but treat each method as its own series. A DEXA scan, smart scale, tape formula, and visual model can use different assumptions, so compare trends within the same method.
Does it work for every body type?
The model is designed for varied adult body types, but individual fat distribution and photo conditions still affect uncertainty. A low-confidence range should be treated cautiously.
Do I need an account?
Not for your first estimate—it runs without sign-in. When you subscribe, a one-tap Google sign-in creates the private account that keeps your baseline, consent records, and numeric progress history. FormCheck does not use your source photo as a profile image or store it.
How many check-ins does a subscription include?
Both plans include up to 5 visual check-ins per calendar month—enough for a weekly photo habit. Unused check-ins do not roll over.