Body fat calculator, using a measuring tape
This uses the US Navy circumference method, so you need a measuring tape and nothing else. It is an estimate rather than a measurement, and it is most useful when you take it the same way every month and watch which direction it moves.
Nothing you type is sent anywhere. The calculation runs in your browser.
Where to put the tape
The method is only as good as the measurement, and the waist is where most people go wrong by pulling the tape tight. Snug against the skin without compressing it, breathing out normally, first thing in the morning.
| Measurement | Where | Common mistake |
|---|---|---|
| Neck | Just below the larynx, tape sloping slightly downward at the front | Measuring over the widest part of the neck rather than below it |
| Waist, men | At the navel, horizontal all the way round | Pulling the tape tight, or holding the stomach in |
| Waist, women | At the narrowest point of the torso, usually above the navel | Measuring at the navel instead of at the narrowest point |
| Hips, women | At the widest point of the buttocks | Measuring at the hip bone rather than the widest point |
How far off a tape measure actually is
The US Army tested this against a real scan. They measured 1,904 serving soldiers by DXA, the reference method, and compared it with the circumference equations and with bioelectrical impedance — the technology in every gym's body composition machine.
Both came out low. The three-site circumference equation, which is the family this page uses, sat about 5.9 percentage points below the scan for men and 4.4 below it for women. That is not a rounding error. If this page says 22%, a DXA scan of the same person would plausibly say something closer to 28%.
Two things follow. The first is not to read the number as a measurement: it is an index. The second is that it is still useful, because a method that is consistently low is still consistently low next month, and the change is what you were watching anyway. A tape that says 22% and then 19% has told you something true even if neither figure is exactly right.
The same study found the newer single-site equation held its accuracy more evenly across sex and ethnicity than the three-site one did, which is a reminder that these equations were fitted to particular populations and carry that with them.
Why I ask for your waist as well
A body fat percentage is a useful number to watch over months and it tells you very little on its own. The waist measurement tells you something the percentage does not, which is where the fat is sitting, and that matters more for an Indian body than for most.
South Asians tend to carry more body fat, and more of it around the organs, at the same weight and the same BMI as European bodies. That is why Indian guidance uses a lower BMI threshold, treating 23 as overweight where the international figure is 25, and why a waist above 90 cm in men and 80 cm in women is treated as raising risk. There is more on that on the BMI calculator with Asian-Indian cut-offs and on how to lose belly fat.
The reading I would rather you track is a waist that comes down while the weights you lift go up. That combination is fat loss with the muscle kept, and it is what the fat loss coaching here is built around.
Body fat: common questions
- How do I measure body fat at home?
- With a measuring tape and this calculator. It uses the US Navy circumference method, which estimates body fat from your height, neck and waist, plus hips for women. It needs no calipers and no machine. It reads low rather than high: tested against DXA scans in 1,904 soldiers, circumference equations of this family came out roughly 4 to 6 percentage points under the scan. Measure first thing in the morning, before eating, with the tape snug and not squeezing.
- How accurate is the Navy body fat method?
- Reasonably accurate for tracking change over months, and less accurate as a single absolute number. The error is not random: measured against DXA in a study of 1,904 soldiers, equations of this type ran about 5.9 percentage points low in men and 4.4 low in women. Because it is consistently low it still tracks change well, which is what it is for. The useful way to use it is to measure the same way every month and watch the direction, rather than to treat one reading as a fact about your body.
- What is a healthy body fat percentage for Indians?
- The commonly used bands put roughly 8 to 20 percent for men and 21 to 33 percent for women in the healthy range, with athletes lower. South Asian bodies tend to carry more fat, and more of it around the organs, at the same weight and BMI as European bodies, which is why Indian guidance uses lower thresholds for BMI and waist. Treat the bands as a guide and your waist measurement as the number that matters most.
- Is body fat percentage better than BMI?
- For an individual, generally yes, because BMI cannot tell muscle from fat and reads a trained person as overweight. Body fat percentage at least tries to separate the two. Neither is a target in itself, and if you are training the more useful signals are your waist measurement and whether the weights you lift are going up.
- How fast can I lower my body fat?
- A rate of roughly half a percentage point a month is a sensible pace that keeps the muscle you have. Faster than that generally means you are losing muscle alongside the fat, which lowers what you burn at rest and makes the weight easier to regain. There is more on why that happens on the page about regaining weight after dieting.
- Can you measure this for me at the gym?
- Yes. Measurements taken by the same person each time are more consistent than measurements you take on yourself, which matters when you are tracking a change of half a percentage point. Both branches, Adajan and Katargam. Call +91 98790 69960.
This is an estimate from a tape measure and it is general information rather than medical advice. No circumference method separates fat from muscle perfectly, and none of them replaces a clinical assessment if you have a medical reason to need one.
The research this page rests on
-
International Journal of Obesity, McClung HL and colleagues, 2025 · 1,904 active-duty US Army soldiers (643 women), body fat measured by DXA, bioelectrical impedance and two circumference equations
Both the circumference equations and bioelectrical impedance underestimated body fat against DXA. The three-site equation, the family this calculator uses, sat 5.88 percentage points below the scan in men and 4.39 below in women. A newer single-site equation held its accuracy more evenly across sex, age and race or ethnicity, which is the clearest evidence that these equations carry the population they were fitted on.
-
Diabetes Care, Zethof M and colleagues, 2021 · 21,072 adults in Amsterdam, including 2,956 of South Asian Surinamese origin and 4,452 of Dutch origin
Waist-to-hip ratio was the most precise predictor of type 2 diabetes in both men and women, and the association between body composition and diabetes was roughly the same across every ethnic group studied. That is a useful corrective: South Asians reach risk at a lower BMI, but per unit of change the relationship is not exotic. It is also the strongest argument on this page for measuring your waist and hips rather than trusting a percentage.
Have it measured properly instead
The same person taking it each month is more consistent than measuring yourself. Call +91 98790 69960.