Exclusively on iPhone

Your body.
Decoded.

The only app that tracks FFMI, body fat percentage, and progress photos with scientific accuracy. Know exactly where you stand.

4.9 on App Store
10K+ active users
Privacy first

Built for serious athletes

Stop guessing. Start knowing. Track what actually matters.

FFMI Tracking

Know your genetic potential. Track lean muscle without the guesswork.

±0.1 accuracy

Progress Photos

AI-powered background removal. Consistent angles. See real changes.

92% stick to it

30-Second Logging

Navy method calculations. Apple Health sync. Done before your coffee cools.

10x faster
Lightning Fast

Log in seconds.
Track for life.

Smart Calculations

Navy method auto-calculates body fat percentage from measurements

Apple Health Sync

Weight automatically pulled from your Apple Watch or smart scale

Progress Photos

AI removes background for perfect before/after comparisons

9:41

Dashboard

Fat-Free Mass Index

21.4

Excellent
87th percentile for natural athletes

Body Fat

12.3%

↓ 0.5%

Weight

180 lbs

→ 0.0

Weekly Progress

+2.3%

Streak

45 days

Why professionals choose LogYourBody

See how we stack up against generic fitness apps

Feature
LogYourBody
Others
FFMI Calculator
Progress Photo AI
Apple Health Syncpartial
Trend Predictions
Privacy First
No Ads Ever
Expert Support
Offline Modepartial

Trusted by experts and athletes

Join thousands who've discovered smarter body composition tracking

"Finally, an app that tracks what actually matters for body composition. I recommend it to all my patients."

👩‍⚕️
Dr. Sarah Chen
Sports Medicine

"The FFMI tracking helped me understand my genetic limits. Game changer for natural athletes."

💪
Mike Rodriguez
Natural Bodybuilder

"My clients love the progress photos feature. Seeing changes they miss in the mirror keeps them motivated."

🏃‍♀️
Emma Wilson
Fitness Coach
4.9★
App Store Rating
10K+
Active Users
500K+
Measurements Logged
99.9%
Uptime

Start tracking what matters

Join thousands of athletes who've stopped guessing and started knowing. Download LogYourBody and see your true progress.

No ads, ever
Your data stays private
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