BMI Calculator

A quick, calm view of your body mass index — informational only, never a diagnosis.

Inputs

Result

Your BMI
22.9
Healthy

Visual breakdown

Underweight<18.5Healthy18.5–24.9Overweight25–29.9Obese30+

Your value: 22.9

Formula

BMI = weight (kg) ÷ height² (m²). Imperial = (lb ÷ in²) × 703.

Example

175 cm and 70 kg → 70 ÷ 1.75² = 22.9 (Healthy).

How to use

  1. Choose metric or imperial units.
  2. Enter your height and weight.
  3. Read your BMI and the band on the meter.
  4. Treat the result as a rough screen — not a diagnosis.

When it's useful

  • Quick check of your weight band against the WHO ranges.
  • Tracking BMI over months alongside other health markers.
  • Pairing with body-fat % or waist size for a fuller picture.
  • A starting point before talking to a clinician.

Common examples

Adult, healthy
175 cm / 70 kg → BMI 22.9 (Healthy).
Adult, overweight
180 cm / 90 kg → BMI 27.8 (Overweight).
Imperial
5′9″ / 154 lb → BMI ≈ 22.7 (Healthy).
Athlete caveat
Muscular athletes often score “Overweight” despite low body fat.

Frequently asked

Is BMI accurate for everyone?

No — BMI doesn't distinguish muscle from fat and isn't ideal for athletes, the elderly, or pregnant people. Use it as a rough screen, not a diagnosis.

What's the healthy range?

WHO defines 18.5–24.9 as the healthy range for adults; this varies for children and some populations.

What about waist size or body fat?

Waist-to-height ratio and body-fat percentage are often better health signals than BMI alone — consider tracking those alongside it.

Does BMI work for kids and teens?

Not directly — children use age- and sex-specific BMI percentiles from a pediatric chart.

How often should I recheck?

Monthly is plenty. Daily weight swings come from water and food, not real change.

What if I'm pregnant?

Standard BMI doesn't apply during pregnancy. Your clinician will track weight gain against pregnancy-specific guidance.

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More health

Informational only — not medical advice. Talk to a clinician for any health decisions.