01
Measure relaxed
Stand naturally and avoid pulling the tape tight enough to compress skin.
Free body composition calculator
Body fat percentage calculator.
Estimate body fat from tape measurements, then use the result to set smarter protein, calorie, and tracking targets. No account needed.
Use this instead of guessing from scale weight.
- Use neck, waist, height, and optional hip measurements.
- Estimate lean mass and fat mass from body weight.
- Connect the estimate to protein, calories, and meal tracking.
Calculator
Estimate body fat
ft
in
lb
in
in
Use a soft tape. Neck sits below the Adam's apple, waist at the narrowest point or navel, and hips at the widest point when needed.
Estimated body fat
20.9%
Average range
This is a tape-measure estimate, useful for trend tracking and choosing better nutrition targets than BMI alone.
Lean mass estimate
178 lb
Approximate body weight that is not fat mass.
Fat mass estimate
47 lb
Approximate fat mass from the tape estimate.
Nutrition planning hint
~2325 kcal/day
A rough lean-mass-based starting point for a moderate fat-loss target. Use TDEE and real tracking before treating it as the plan.
Turn the estimate into meals.
Use the result to choose protein, calorie targets, and a tracking workflow that shows whether the trend is moving.
Repeat measurements under the same conditions. The trend matters more than one perfect reading.
How to use it
Measure the same way every time.
02
Use the right sites
Men use neck and waist. Women use neck, waist, and hips.
03
Track the trend
Repeat measurements under similar conditions instead of reacting to one reading.
04
Plan from the result
Use protein, calorie, and macro calculators to turn the estimate into a food target.
Formula
Methodology
This calculator uses the U.S. Navy circumference method. For men, it uses height, neck, and waist. For women, it also uses hip circumference.
The formula estimates body density from tape measurements and converts that estimate into body fat percentage. It is fast and practical, but it is still an estimate.
Body fat percentage is useful because it makes the next nutrition step clearer: protect lean mass with protein, choose a realistic calorie target, and track the day consistently.
Example
225 lb with a 38 in waist and 16 in neck
The calculator estimates body fat percentage, lean mass, and fat mass so the user can move into protein, calorie, and macro planning instead of only watching scale weight.
FAQ
Common body fat questions
How does this body fat calculator work?
It uses the U.S. Navy circumference method. Men enter height, neck, and waist. Women enter height, neck, waist, and hips. The result is an estimate, not a scan.
Is the Navy body fat formula accurate?
It is useful for a quick at-home estimate and trend tracking, but it can be off for individual builds. Use the same measurement method over time and compare the trend.
Is body fat percentage better than BMI?
For many fitness and nutrition decisions, body fat percentage is more useful than BMI because it separates lean mass from fat mass instead of only comparing height and weight.
How should I use this number for weight loss?
Use it as context. Pair the estimate with TDEE, protein intake, and real intake tracking before changing calories aggressively.
Next calculator steps
Keep the math moving in the right order.
Daily follow-through
Turn the calculator result into daily tracking.
The calculator helps you choose the number. IntakeCalc helps you see whether today’s meals actually fit it.
Track body composition