BMI calculator
One number, and what it is worth.
Examples temporarily replace the input and settings. You can restore your previous work.
Your files stay on your device
This tool runs entirely in your browser. What you paste is processed on your device and is never sent to a server, so it is safe to use with tokens, keys and unpublished text.
Example
Worked example — BMI calculator
Use the following inputs and settings. Keep other settings at the page defaults.
| Item | Value |
|---|---|
| Height | 170 |
| Weight | 65 |
| Compare against | The WHO bands (used in most countries) |
| Output | BMI 22.5 |
| Output | a healthy weight |
| Output | Height 170.0 cm |
| Output | Weight 65.0 kg |
| Output | Healthy range 53.5–72.3 kg at this height |
| Output | WHO bands. Japan’s are stricter: 25 and over is already 肥満 there, not merely overweight. |
Expected result — BMI 22.5
How it works
- Type your height — 170, 1.7 m, or 5ft 7in all work.
- Type your weight — 65, 65 kg or 143 lb.
- Read the BMI and the band it falls in.
- Switch to the Japanese bands if that is the standard you are being measured against.
Frequently asked questions
- Why do the Japanese bands differ?
- Because the health risks appear at a lower BMI in East Asian populations, so JASSO calls 25 and over obese where the WHO calls 25–30 overweight and 30 the start of obesity. If you have had a 健診 in Japan, the Japanese bands are the ones your result was read against.
- Is BMI actually useful?
- As a rough population measure, yes. For one person it is weak: it cannot tell muscle from fat, so athletes come out “overweight”, and it says nothing about where the weight sits, which is the part that matters most for risk. Waist measurement adds more than a second decimal place of BMI ever will.
- Does it work for children?
- No. Children are measured against age-and-sex percentile charts, not against fixed bands, because the healthy range moves as they grow. A number from this page would be meaningless for them.
- Can I type imperial?
- Yes — 5ft 9in and 160 lb are read directly, no converting first. Mixing them is fine too.
- Is anything uploaded?
- No. It runs in your browser, so what you type stays on your computer.
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