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Ideal weight calculator
Curious what a healthy weight looks like for your height? This gives a sensible range rather than a single magic number. It derives the range from the standard healthy BMI band of 18.5 to 24.9 applied to your height, and adds one reference weight from the Devine formula, a figure clinicians sometimes use for dosing and quick benchmarks. Enter your sex and height in metric or imperial. Read it as a broad guide to aim within, shaped by your own build and muscle, not a target to chase to the kilogram.
The range is a BMI of 18.5 to 24.9 for your height. It is a guide, not a target; muscle, build and age all matter.
How it works
- Enter your sex and height. Metric and imperial are both accepted and converted as needed.
- The healthy range is the weight that puts your BMI at 18.5 (lower bound) up to 24.9 (upper bound) for your height.
- In practice that is BMI x height(m) squared at each end of the band.
- The Devine figure is a separate single reference weight, calculated from height and adjusted by sex, common in clinical settings.
healthy range = 18.5 x height(m)^2 to 24.9 x height(m)^2
A healthy weight is read off the standard BMI band. The lower bound multiplies a BMI of 18.5 by your height in metres squared, and the upper bound does the same with 24.9. Because height is squared, a small change in height moves both ends of the range noticeably. The Devine figure is a separate single weight derived from height and adjusted by sex, used mainly in clinical dosing.
- height(m)
- your height in metres
- 18.5
- BMI at the lower edge of the healthy band
- 24.9
- BMI at the upper edge of the healthy band
How BMI bands are labelled
| Underweight | BMI below 18.5 | |
| Healthy weight | BMI 18.5 to 24.9 | |
| Overweight | BMI 25 to 29.9 | |
| Obese | BMI 30 and above |
Worked example
For a height of 175 cm: a healthy range of roughly 57 to 76 kg. The lower end reflects a BMI of 18.5 and the upper end 24.9. Someone at 160 cm would see a lower band, around 47 to 64 kg.
Key facts
- Because weight scales with height squared, two people of healthy weight can differ by 30 kilograms or more.
- BMI was devised for populations, not individuals, so it reads muscle and fat as the same kind of mass.
- The healthy band is deliberately wide, spanning roughly a 20 kilogram range at average adult heights.
- The Devine formula dates from 1974 and was built for drug dosing rather than as a weight goal.
Tips
- Aim to sit somewhere inside the band rather than at one exact figure, and let your build guide where.
- Pair the result with a waist measurement, which often flags health risk that BMI alone misses.
- If you carry a lot of muscle, expect the upper band to understate a healthy weight for you.
- Track changes in how clothes fit and energy levels alongside the scale, not the number on its own.
Healthy weight range by height
| Height | Lower (kg) | Upper (kg) |
|---|---|---|
| 155 cm | 44 | 60 |
| 165 cm | 50 | 68 |
| 175 cm | 57 | 76 |
| 185 cm | 63 | 85 |
Frequently asked questions
Is BMI a flawless measure?+
No. It cannot tell muscle from fat, so very muscular people may read as overweight despite low body fat. Use the range alongside other signals such as waist size, and consult a health professional if a result surprises you.
Where in the range should I aim?+
There is no single correct point. Build, muscle mass, age and overall health all influence where a healthy weight sits for you. Treat the span as a guide rather than a precise goal.
Why show a range and a single number?+
The BMI range reflects that healthy weight is genuinely a band, not one value. The Devine figure is included only as a familiar clinical reference point, not as the "right" weight.
Does it apply to children or athletes?+
Not really. Under-18s need age and sex specific charts, and heavily trained athletes carry muscle the formulas do not account for. For those cases, professional assessment is more reliable.
Things to watch
- This is general guidance, not medical advice; a health professional can judge what is right for your build and history.
- BMI bands do not fit under-18s, pregnant women or heavily trained athletes, who need a different assessment.
- A figure inside or outside the band is not a diagnosis on its own; other measures matter too.
Sources
- Obesity and overweight: BMI and healthy weight · World Health Organization
Last updated: 2026
This is an estimate for general guidance, not financial, tax, legal or medical advice. Figures can change and individual circumstances vary. Always confirm with the official sources listed before making decisions.
- This is general guidance, not medical advice.
- Based on population BMI bands, which do not capture body composition or individual health.
- Not suitable for under-18s, pregnancy, or competitive athletes.
Reviewed by Vikas Dulgunde.