LeanTrack: Body Fat Calculator

Know what your weight can't tell you.

Weight alone says nothing about what your body is actually made of. Two people at the same weight can look completely different — the difference is body fat. LeanTrack calculates your body fat percentage using four proven formulas, saves every result, and shows you exactly which way you are heading.

FOUR WAYS TO MEASURE
• U.S. Navy — tape measure only (neck, waist, plus hips for women)
• BMI method — Deurenberg formula, no equipment needed
• Jackson-Pollock 3-site — skinfold caliper
• Jackson-Pollock 7-site — the most thorough caliper protocol

Pick the method that fits the tools you have. All four are included.

MORE THAN ONE NUMBER
Every calculation gives you the full picture:
• Body fat percentage with category (Essential, Athlete, Fitness, Average, Obese)
• Fat mass and lean mass
• BMI and FFMI (fat-free mass index)
• BMR — Mifflin-St Jeor and Katch-McArdle
• TDEE based on your activity level
• Your fitness range and the typical value for your age

SET A GOAL, WATCH IT GET CLOSER
• Choose a target body fat percentage
• A progress ring shows how far you have come
• See your weekly rate of change
• Get an estimate of how many weeks are left at your current pace

SEE THE TREND, NOT JUST TODAY
• Every saved result is charted over time
• Filter by 1, 3, 6 months or all time
• Waist circumference tracked as a second trend line
• Full history you can review and delete anytime

MEASURE IT RIGHT
Inconsistent results usually come from inconsistent measuring. Built-in guides show exactly where to place the tape, how to read a caliper, and when to measure so your numbers stay comparable week after week.

BUILT THE WAY IT SHOULD BE
• Completely free — every feature, no paywall, no locked methods
• No ads
• No account and no sign-up
• Works fully offline — the app requests no permissions at all, not even internet
• Your measurements never leave your phone
• Metric and imperial units
• English, Azerbaijani, Turkish and Russian

Note: LeanTrack calculates body fat from measurements you enter yourself. It does not use the camera or any sensor. All formulas produce estimates, not a medical diagnosis or medical advice. For health decisions, please talk to a qualified professional.