What your BMI means
| BMI | Category (adults) |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Healthy weight |
| 25 – 29.9 | Overweight |
| 30 or more | Obesity |
These are the adult categories used by the World Health Organization and the CDC. Body mass index is your weight in kilograms divided by your height in metres squared. It is a quick, free way to screen whether your weight may be affecting your health, which is why doctors and public-health bodies use it.
What BMI doesn’t tell you
BMI only looks at height and weight. It can’t tell muscle from fat, so strong, muscular people often score as overweight while being lean. It doesn’t show where you carry fat, and fat around the waist matters more for health than fat elsewhere. Age, sex and ethnicity also change what a given BMI means. Treat your number as a starting point for a conversation, not a verdict.
Your healthy weight range
The range shown under your result is the weight that would put you at a BMI of 18.5 to 24.9 at your height. It is wide on purpose: two people of the same height can be healthy at very different weights depending on their build and muscle. If you are above the range, you don’t need to reach the bottom of it. Moving towards the top of the range, or simply losing a few kilos and keeping them off, is a realistic and worthwhile goal.
If you want to change your BMI
- Lowering BMI means losing weight, which comes from a steady calorie deficit. Find your numbers with the calorie calculator.
- Pair it with strength training so the weight you lose is fat, not muscle. The home workouts in Thrive Fit need no equipment.
- Pick a way of eating you can keep. Our free 7-day meal plans include weight loss, high-protein and Mediterranean options.
- Aim for slow, steady change. Losing 5–10% of your body weight already brings real health benefits for many people.
The Thrive Fit app tracks your weight and BMI over time, so you see the trend rather than one number. Read how we calculate it on our health sources page.
