HelloCalcSabaiTH

BMI Calculator

Calculate Body Mass Index from weight and height using the Asian criteria (Thai Ministry of Public Health) or WHO international criteria, with your healthy weight range.

Rough estimates for adults, not a medical diagnosis. Talk to a doctor or dietitian before changing your diet or exercise.

Sex
yrs
cm
kg
More details (optional) — for more accurate results
cm
cm
cm
%
bpm

BMI (Body Mass Index)

–
Weight for a normal BMI
–

BMR (resting metabolism)

–kcal/day

TDEE (daily calories)

BMR from the chosen formula × activity level ()

–kcal/day (maintain weight)
Goalkcal/day

Body fat %

–
Fat mass
–
Lean mass
–

Waist-to-height ratio

–
Waist should not exceed
–

Add your waist (measured at the navel) under More details to see the ratio. The Thai guideline is a waist no more than half your height.

Ideal weight

–kg

Daily water

–litres/day
From body weight ()
–
Extra for activity
–
Glasses of 250 ml
–

Includes water from food and other drinks. Drink more in hot weather or when sweating. People with kidney or heart conditions should ask a doctor.

Daily protein

–g/day
For your activity level
–
Per meal (3 meals)
–

Examples: 1 egg ≈ 6 g · 100 g chicken breast ≈ 31 g · 1 glass of milk ≈ 8 g · 100 g firm tofu ≈ 8–15 g

Max heart rate

–bpm

    How it works

    Enter your height (cm) and weight (kg) to get your BMI and category instantly. The default is the Asian criteria, which suit Thai and other Asian people. Switch to WHO international criteria to compare.

    Formula

    BMI = weight (kg) ÷ height (m)²

    Example: 65 kg at 1.70 m → 65 ÷ 2.89 = 22.5

    BMI categories

    Asian criteria (Thai MoPH)
    Underweight< 18.5
    Normal18.5 – 22.9
    Overweight23 – 24.9
    Obese I25 – 29.9
    Obese II≥ 30
    WHO international criteria
    Underweight< 18.5
    Normal18.5 – 24.9
    Overweight25 – 29.9
    Obese class I30 – 34.9
    Obese class II35 – 39.9
    Obese class III≥ 40

    FAQ

    What BMI counts as obese?

    Under the Asian criteria used by the Thai Ministry of Public Health, a BMI of 23–24.9 is overweight and 25 or more is obese. Under WHO international criteria, 25–29.9 is overweight and 30 or more is obese.

    Why are the Asian cut-offs lower?

    Studies show Asian people tend to have more body fat and face higher risks of diabetes, high blood pressure and heart disease at a lower BMI than Western populations, so WHO recommends lower cut-offs for the Asia-Pacific region.

    Does BMI work for everyone?

    It is meant for adults 18 and over. It is not suitable for children, pregnant women, the very elderly or very muscular athletes, because BMI cannot tell fat from muscle. Look at body fat % and waist size too.

    What waist size is healthy?

    The Thai Ministry of Public Health recommends a waist no more than half your height. For example, at 170 cm tall your waist should be no more than 85 cm.

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