Body Fat Calculator
Calculate macronutrient ratios and daily targets for protein, carbohydrates, and fats.
Body Measurements
Uses circumference measurements (neck, waist, hip) - most accurate
Feet
Inches
Measure around the neck, just below the Adam's apple
Measure at the narrowest point, usually just above the navel
📏 Measurement Tips
- • Measure in the morning before eating
- • Keep tape measure snug but not tight
- • Take measurements at the same time of day
- • Use a flexible tape measure
- • Have someone help you for accuracy
Body Fat Results
Body Fat Percentage
Athletic range
Body Fat Mass
Fat weight
Lean Body Mass
Muscle, bone, organs
Body Fat Categories (Men)
Method Details
Body Fat Tips
- • Focus on overall health, not just body fat percentage
- • Combine cardiovascular and strength training
- • Diet accounts for 70-80% of body composition changes
- • Take progress photos and measurements regularly
- • Consider professional body composition analysis
How it works
Body-fat percentage tells you how much of your weight is fat versus lean mass (muscle, bone, water) — a far better health signal than weight or BMI alone. This calculator uses the U.S. Navy method, which estimates body fat from a few tape-measure circumferences and your height.
U.S. Navy method (men)
%BF = 86.010·log₁₀(waist − neck) − 70.041·log₁₀(height) + 36.76
- waist
- waist circumference (women also measure hips)
- neck
- neck circumference
- height
- standing height (same units as the circumferences)
Worked example
- Man, height 70 in
- Waist 34 in, neck 16 in
- log₁₀(34 − 16) = log₁₀(18) ≈ 1.255
- %BF = 86.010×1.255 − 70.041×log₁₀(70) + 36.76
Body fat ≈ 15% — in the “fitness” range for men.
Good to know
- Healthy ranges differ by sex: roughly 10–20% for men and 18–28% for women; essential fat (the minimum) is ~3% and ~12% respectively.
- The Navy method is convenient but approximate. Calipers, bioelectrical impedance (BIA) scales, and DEXA scans get progressively more accurate (and expensive).
- Track the trend over weeks rather than obsessing over a single reading — measurement noise can swing any one estimate by a few points.
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Frequently Asked Questions
What are good macro ratios for weight loss?
Higher protein (25-35%), moderate carbs (30-40%), moderate fat (25-35%). Protein helps preserve muscle during weight loss and increases satiety.
How much protein do I need daily?
Active individuals need 0.8-1.2g per pound of body weight. Strength athletes may benefit from 1.2-1.6g per pound for muscle building and recovery.
Should I track macros or just calories?
Start with calories for weight management, then add macro tracking for body composition goals. Protein is the most important macro to track consistently.
How often should I exercise?
The WHO recommends at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic activity per week.
What is a balanced diet?
A balanced diet includes variety from all food groups: fruits, vegetables, whole grains, lean proteins, and healthy fats.
How much water should I drink?
General recommendation is 8-10 glasses (2-2.5 liters) per day, adjusted for activity level and climate.
How important is sleep?
Sleep is crucial for physical recovery, mental health, and overall wellbeing. Adults need 7-9 hours nightly.