Ideal Weight Calculator

This calculator provides estimated ideal body weight (IBW) values using multiple standard clinical formulas. Ideal weight is a reference point used in clinical practice for considerations such as medication dosing and basic health assessment. It is not an absolute measure of health for any specific individual but a useful starting point for conversation with a healthcare professional.

The formulas implemented here — Devine, Robinson, Miller and Hamwi — were developed to estimate a reasonable target weight given a person's height and, in some formulas, gender. Each formula applies slightly different constants and slopes, which is why the resulting numbers can differ modestly. The tool also displays a BMI-based healthy weight range (BMI 18.5–25) so you can compare formula outputs with population-based guidance.

How to interpret results

Use the Devine and related formula outputs as approximations rather than strict prescriptions. For medication dosing in clinical settings, some providers rely on the Devine formula; for lifestyle goal-setting, the BMI range may be more practical. If you have a muscular build or specific health conditions, consider body composition testing or professional assessment to better understand your optimal weight.

Practical examples and considerations

For an individual 170 cm tall, different formulas will give similar but not identical results — the Devine formula may give one value while the Miller or Robinson formulas give slightly higher or lower estimates. The BMI-based healthy range gives a span of weights that many clinicians consider acceptable for general health. Use the range and multiple formula outputs together to form a balanced expectation rather than relying on a single number.

Limitations and next steps

These formulas do not account for age-related changes, fat distribution, or underlying medical conditions. If results prompt concern or if you need individualized targets for performance or medical therapy, consult a clinician or registered dietitian. They can incorporate measurements like waist circumference, body fat percentage, and clinical history to make personalized recommendations.

This tool is intended for informational use and runs entirely in your browser; it does not transmit personal data to the server. For any medical decisions, always consult a healthcare professional.