A practical estimate you can do at home. Pick your method, enter the required measurements, and get your % body fat.
Reviewed by João Freitas · Formulas: US Navy + Jackson–Pollock (Siri)
The biggest source of error is technique. The goal is not a perfect number — it's a repeatable method you can track over time. Measure under the same conditions (same time of day, similar hydration, no pump) every 2–4 weeks.
There's no single perfect "body fat test" at home. These calculators use statistical models that turn measurements into an estimate. If you use the same method, same landmarks, and similar conditions, the result is very useful for tracking trends.
Uses height plus body circumferences (neck/waist, and hip for women). Works surprisingly well because waist-to-neck ratios correlate with overall fatness. Less accurate if fat distribution is unusual or measurements are inconsistent.
Measures skinfold thickness at three standardized sites (different for men and women). Estimates body density and converts it to body fat % using the Siri equation. Accuracy depends heavily on technique.
Tape is less reliable if you carry fat very differently from the average person the equations were built on (very muscular neck/shoulders, very high obesity, extreme leanness). Bloating, big meals, and inconsistent tape tension also add noise. Use it mainly to track trends under the same conditions.
Calipers struggle if you can't get a clean pinch (very high body fat), if measurements are taken right after training/heat, or if site location is inconsistent. Inter-tester differences are common. If possible, have the same person measure you each time and average 2–3 repeats per site.
Plages de référence générales de l'American Council on Exercise (ACE). Les plages saines varient selon l'âge, le sport et la génétique — utilise-les comme repère, pas comme verdict.
| Catégorie | Hommes | Femmes |
|---|---|---|
| Masse grasse essentielle | 2–5% | 10–13% |
| Athlètes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Acceptable / moyen | 18–24% | 25–31% |
| Obésité | 25%+ | 32%+ |
They use different models and assumptions. Fat distribution, hydration and technique can shift results. Pick one method and repeat it consistently.
Double-check units, re-measure carefully, and average 2–3 repeats. If you recently trained, ate a big meal, or are dehydrated, wait and measure again under normal conditions.
Every 2–4 weeks is a good balance. More often can be noisy due to water retention and measurement variability.
It's an estimate based on population data. For many people it's "accurate enough" to track changes, especially if you measure consistently. If your fat distribution is unusual, results can be biased — use it mainly for trends, not absolute precision.
Yes. Both methods on this page work without body weight. Tape uses circumferences; calipers use skinfold thickness. You still need height.
Tape is simpler and often more repeatable. Calipers can be more sensitive if your technique is consistent. Pick one method and stick with it.
Lis le guide complet du TDEE →
Disclaimer: educational purposes only. Not medical advice. If you have a medical condition, talk to a qualified professional.
Ads help keep this tool free. If you can, disable your ad blocker for this site and refresh the page.