Is the BMI formula different for women?

The same formula (weight ÷ height²) applies to both sexes, and the WHO categories are the same for everyone, even though women typically carry about 10 percentage points more body fat than men at the same BMI.

What is a healthy BMI for a woman?

The WHO healthy range (18.5–24.9) applies to adult women. Some research suggests that women may be at lower health risk at slightly higher BMIs than men, but the WHO thresholds are the standard reference.

Does BMI change with age for women?

The BMI formula does not change, but body composition changes with age. After menopause, women tend to gain body fat and lose muscle mass, which may affect how BMI reflects actual health risk.

Does the calculator keep what I enter?

The values exist only in the open page and are not written to browser storage, so reloading the page clears them. All calculations run in your browser. Our servers are not involved at any point.

BMI calculator for women

BMI uses the same formula for men and women, but body composition differs: women naturally carry a higher percentage of body fat at the same BMI. Enter your details to see your BMI, WHO category, and healthy weight range for your height.

Height (cm)

Weight (kg)

Results are for informational purposes and do not constitute medical advice.

How it works

Your inputs are normalised to kilograms and metres if you use imperial units, then the WHO formula weight(kg) / height(m)^2 returns your BMI. The same number drives the WHO category label, and the calculator also runs the formula in reverse using the 18.5 to 24.9 healthy range to display the weight band that corresponds to a healthy BMI at your height.

Processing runs in your browser

All calculations happen locally in your browser tab. Our servers are not involved at any point.

Technical specification

The BMI formula was standardised by the WHO Technical Report Series 894 (2000): BMI = weight(kg) / height(m)². WHO classifies BMI into four categories for adults: Underweight (<18.5), Normal weight (18.5–24.9), Overweight (25.0–29.9), and Obese (≥30.0). BMI does not distinguish between muscle and fat mass and is intended as a population-level screening tool, not an individual diagnostic.

Formula: weight(kg) / height(m)²
Standard: WHO Technical Report Series 894 (2000)
Normal range: 18.5 – 24.9
Browser API: Pure JavaScript arithmetic. No library

Related operations

To estimate daily energy needs, try the calorie calculator. For body composition with circumference measurements, use the body fat calculator. To find a reference weight range for your height, see the ideal weight calculator.

Frequently asked questions

Is the BMI formula different for women?: The same formula (weight ÷ height²) applies to both sexes, and the WHO categories are the same for everyone, even though women typically carry about 10 percentage points more body fat than men at the same BMI.
What is a healthy BMI for a woman?: The WHO healthy range (18.5–24.9) applies to adult women. Some research suggests that women may be at lower health risk at slightly higher BMIs than men, but the WHO thresholds are the standard reference.
Does BMI change with age for women?: The BMI formula does not change, but body composition changes with age. After menopause, women tend to gain body fat and lose muscle mass, which may affect how BMI reflects actual health risk.
Does the calculator keep what I enter?: The values exist only in the open page and are not written to browser storage, so reloading the page clears them. All calculations run in your browser. Our servers are not involved at any point.

Last reviewed September 30, 2026

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