Waist to Height Ratio Calculator (WHtR)

Waist-to-height ratio is one division and one message: keep your waist under half your height. No tables, no sex-specific columns, no age bands. Measure both in the same units and enter them below.

Why one number covers everyone

A systematic review by Browning, Hsieh and Ashwell pooled studies from fourteen countries covering white, Asian and Central American populations and found weighted mean boundary values of 0.50 for men and 0.50 for women, across every cardiometabolic outcome examined. The finding survived the differences in build that force waist circumference to carry separate cut-offs by sex and by ethnicity.

That is what makes the ratio unusually easy to teach. A 5 ft 10 in adult (178 cm) should aim to keep the waist under 35 inches (89 cm) — a target you can work out in your head without looking anything up.

WHtR	How to read it
Under 0.40	Below the expected range
0.40 to 0.49	Healthy
0.50 to 0.59	Elevated
0.60 or above	Substantially elevated

The military moved to this in 2026

If you arrived here searching for an Army or Air Force calculator, this is why. HPRC, the human performance resource run by the Uniformed Services University, states that as of January 1, 2026 the military uses the waist-to-height ratio method to assess body composition, with the waist taken at the midpoint between the top of the hip bone and the lowest rib, divided by height.

That replaced the height-and-weight screen as the first gate. Circumference-based body fat estimation did not disappear — it became the follow-up assessment for people the ratio flags, which is what allows a heavily muscled service member to clear a screen they would have failed on weight alone. Each service publishes its own screening value and its own measurement protocol in its current instruction, so check the one that governs you rather than any calculator, including this one.

The one to run afterwards, if you want to see what the secondary assessment estimates, is the Navy body fat calculator.

The argument for a higher cut-off

The 0.5 rule is not unanimous. A 2024 Nutrients analysis of 3,566 NHANES participants surveyed between 2011 and 2018 argued that 0.5 is probably too low for people already classified as overweight, and derived higher optimal values in every group it examined:

Group	Men	Women
White	0.57	0.58
Black	0.55	0.57
Asian	0.56	0.59
Hispanic	0.57	0.59

Both positions can be right at once, because they answer different questions. As a public health message aimed at everyone, 0.5 is deliberately conservative and easy to remember. As a diagnostic threshold inside an already-overweight population, it flags almost everybody and stops discriminating.

Measuring so the ratio means something

The division is trivial; the tape is not. Stand upright, breathe out normally, and place the tape level all the way around — a tape that rides up at the back inflates the reading. Measure over bare skin or a thin layer, take it twice, and use the average.

Consistency beats precision here. An inch of drift in where you place the tape moves the ratio by about 0.015, which is enough to shift a borderline result across a line. For the raw measurement with its own American threshold, the NHLBI flags a waist over 40 inches (102 cm) in men and over 35 inches (89 cm) in women. For the share of your body that is fat rather than where it sits, the body fat percentage calculator answers the other half.

This content is informational and does not replace evaluation by a health professional.