17 Fit BMI calculator

BMI calculator body mass index and the healthy weight for your height

Q: How much weight should I lose?

Often the first 5–10 % of your weight already makes a difference. 17 Fit suggests a goal and never one below a BMI of 20.

Enter your height and weight to see your BMI, its category by the World Health Organization and the weight range that counts as healthy for your height.

Heightcm Weightkg

How BMI is worked out. Weight in kilograms divided by height in metres squared. For example, 70 kg at 1.75 m: 70 ÷ (1.75 × 1.75) = 22.9.

Your BMI

22.5 kg/m²

Healthy weight

Healthy weight for your height: 53.5–72 kg

Within the healthy range

BMI 22.5: healthy weight.

BMI is one number on one day. 17 Fit follows your weight trend instead of the day‑to‑day swings, suggests a goal and keeps the pace safe — no more than 1 % of your weight a week.

BMI categories

The World Health Organization’s classification for adults.

BMI	Category
under 18.5	Underweight
18.5–24.9	Healthy weight
25–29.9	Overweight
30–34.9	Obesity, class I
35–39.9	Obesity, class II
40 and over	Obesity, class III

Healthy weight by height

The weight at which BMI stays between 18.5 and 24.9.

Height	Healthy weight
150 cm	41.6–56 kg
155 cm	44.4–59.8 kg
160 cm	47.4–63.7 kg
165 cm	50.4–67.8 kg
170 cm	53.5–72 kg
175 cm	56.7–76.3 kg
180 cm	59.9–80.7 kg
185 cm	63.3–85.2 kg
190 cm	66.8–89.9 kg
195 cm	70.3–94.7 kg
200 cm	74–99.6 kg

What BMI doesn’t show

Muscle BMI doesn’t tell muscle from fat: an athlete can come out “overweight” with little body fat.
Where the fat is Fat around the waist matters more than the number on the scales; BMI doesn’t see it.
Age In older adults the same BMI can mean less muscle and more fat.
Pregnancy, children, teenagers BMI for adults doesn’t apply: children and teenagers are judged by growth percentiles.

Questions and answers

Food calories

Updated: 15 October 2026

What is a healthy BMI?

For adults, 18.5 to 24.9. The range is the same for women and men, at any adult age.

Is BMI different for women and men?

The formula and the categories are the same. What differs is body composition, which BMI doesn’t measure.

I go to the gym and my BMI says overweight. Is that right?

It may not be: muscle is heavy, and BMI only knows your weight. A waist measurement or body fat percentage tells you more.

How much weight should I lose?

Often the first 5–⁠10 % of your weight already makes a difference. 17 Fit suggests a goal and never one below a BMI of 20.

How quickly can I reach a healthy BMI?

At a safe pace of up to 1 % of your weight a week. Faster, and you lose muscle too.

17 Fit

Your weight as a trend, not a mood

Daily weigh-ins jump about with water and salt. 17 Fit draws the trend through them and shows where it’s really heading.

Weight trend and a safe pace to your goal
Calories and macros from a photo of your plate
Free food diary, no sign-up and no ads

Progress screen in 17 Fit: the weight trend