Free Tool

Body Fat Calculator

Estimate your body fat percentage with just a tape measure — no calipers, no gym equipment, no guesswork.

US Navy formula

Lean mass breakdown

Category & goal targets

Calculate Body Fat %

Units

Height

Neck

Waist

Body Weight

Measure at the narrowest point for waist. Take measurements in the morning, unflexed. Average 2–3 readings for accuracy.

Estimated Body Fat

—

Where you fall on the scale

Essential Athlete Fit Average Obese

—

kg lean mass
(muscle, bone, water)

—

kg fat mass
(total body fat)

Goal targets for your sex

The US Navy method has ±3–4% error vs DEXA scan. Use as a trend tracker — retest monthly under the same conditions.

Body fat tells you what to change. FitUpToday coaches tell you exactly how — with an Indian meal plan, weekly check-ins, and real accountability.

Get a personalised plan →

Accuracy Tips

How to measure correctly

The US Navy formula is only as accurate as your measurements. Small errors compound. Here's how to take each measurement correctly — and consistently — so your trend data is reliable month over month.

Neck circumference

Measure just below the larynx (Adam's apple), sloping slightly downward at the front. Keep the tape horizontal. Don't flex or tilt your head.

✓ Men only. Measure once — it doesn't change much.

Waist circumference

Measure at the narrowest point between your ribcage and navel — usually around 2 cm above the belly button. Don't suck in. Breathe out naturally and measure at rest.

✓ Most important measurement. Take 3 readings and average.

Hip circumference (women)

Measure at the widest point of the hips and glutes — usually at the level of the greater trochanters (hip bones). Stand with feet together. Keep the tape parallel to the floor.

✓ Women only. Critical for accuracy of the Navy formula.

Height

Measure without shoes, standing straight against a wall. Look straight ahead. Measure from floor to the top of your head. Do this in the morning — you're slightly taller before spinal compression from the day.

✓ Use the same measurement each time.

Measurement methods compared

DEXA ScanGold standard — hospital/lab

±1–2%

Hydrostatic weighingWater displacement — lab

±1–3%

Skinfold calipers7-site professional method

±3–4%

US Navy (this calculator)Tape measure — at home

±3–4%

BIA scales (body weight scales)Bioelectrical impedance

±5–8%

BMI-based estimationHeight + weight only

±8–12%

The Navy method is the most practical accurate tool available without equipment. Its ±3–4% error is consistent — making it reliable for tracking changes over time.

Reference

Body fat categories

Based on American Council on Exercise (ACE) classifications. Where you are determines what protocol to follow.

Essential Fat

Minimum viable

Men

2 – 5%

Women

10 – 13%

The minimum fat required for organ function, hormonal health, and survival. Going below this causes serious health problems — do not target this range.

Athlete

Performance range

Men

6 – 13%

Women

14 – 20%

Competitive athletes and dedicated gym-goers. Requires consistent training and dietary discipline to maintain. Visible muscle definition throughout.

Fitness

Most achievable

Men

14 – 17%

Women

21 – 24%

The ideal long-term target for most people. Healthy, lean, sustainable. Abs visible in good lighting. Reachable in 12–20 weeks with consistent effort.

Acceptable

Average range

Men

18 – 24%

Women

25 – 31%

Medically acceptable but not optimal. Elevated metabolic disease risk begins here. This is where most sedentary adults in their 30s and 40s land.

What To Do With Your Number

Reducing body fat that lasts

Create a Caloric Deficit

Body fat is stored energy. The only way to reduce it is to consistently consume fewer calories than you burn. A deficit of 300–500 kcal/day produces 0.3–0.5 kg of fat loss per week — sustainable and muscle-preserving.

Use the BMR Calculator to find your maintenance calories, then subtract 300–400 kcal for a safe, sustainable deficit.

Protect Muscle With Protein

In a deficit, your body will break down muscle as well as fat — unless you eat enough protein and resistance train. High protein (2.2–2.4g/kg) paired with strength training preserves lean mass while you lose fat.

Use the Protein Calculator for your exact daily target — and hit it every day.

Track Progress Monthly

Body fat changes slowly. Retest every 4 weeks under identical conditions — same time of day, same hydration, same measuring protocol. Don't get caught up in daily fluctuations. Judge results over 4-week blocks.

A 1% reduction per month is excellent progress. At that rate, dropping from 25% to 15% takes ~10 months — realistic and sustainable.

Common Questions

Body fat explained

The US Navy formula typically has a margin of error of ±3–4% compared to DEXA scanning. That means if this calculator says 22%, you might be anywhere from 18–26% on a DEXA. This doesn't make it useless — it's very consistent, so if you retest under the same conditions each month, the change in your reading is reliable even if the absolute number isn't perfectly accurate. Think of it as a trend tracker, not a lab result.

Women and men distribute fat differently — women typically store more fat in the hip and thigh region (gynoid pattern), while men store more around the abdomen (android pattern). Including the hip measurement in the female formula makes the estimate more accurate by accounting for this natural difference. Omitting it in the male formula isn't an oversight — male fat is more uniformly predicted by waist and neck alone.

This is called TOFI — Thin Outside, Fat Inside. You may have a low subcutaneous fat (the fat under your skin that you can see) but high visceral fat (the fat around your organs, which is metabolically dangerous). The Navy formula only estimates total body fat percentage and cannot distinguish between subcutaneous and visceral fat. If you have a desk job, eat a processed diet, or have insulin resistance markers, ask a doctor for a visceral fat assessment.

South Asians have a genetic predisposition to store more visceral fat at lower BMIs — this is well-documented in metabolic research. As a result, the ideal body fat target for Indian adults is slightly lower than Western norms. For Indian men: aim for 10–18% (athlete to fitness range). For Indian women: aim for 18–25%. These ranges are associated with better metabolic markers in South Asian populations. A FitUpToday coach can help you set a realistic personal target.

Sustainable fat loss is 0.5–1% body fat per month. Going faster is possible short-term but almost always leads to muscle loss and metabolic adaptation. For someone at 28% targeting 18%, that's ~10 months of consistent effort — longer than most people expect, but the results last. Rapid fat loss programs that promise 2–3% per month typically result in losing muscle, not fat, and the "after" photos often look worse than slow, steady progress.

No. Women require more essential body fat for hormonal function, fertility, and bone density. The healthy range for women is 18–25% — significantly higher than men's 10–18%. Women who drop below 14–15% body fat often experience disrupted menstrual cycles, reduced bone density, and hormonal imbalances. Chasing very low body fat based on male physique standards is both unhealthy and counterproductive for most women. FitUpToday coaches account for this in every female client plan.

Body Fat Calculator

How to measure correctly

Body fat categories

Reducing body fat that lasts

Body fat explained

You know your number.Now build the plan to change it.

You know your number.
Now build the plan to change it.