Free Ideal Weight Calculator
Updated September 2026
Calculate your ideal body weight range using Devine, Hamwi, Robinson, and Miller formulas. See range across multiple methods — free online tool.
Verified Capabilities
Devine, Robinson, Miller, and Hamwi results are all shown together in kg and lbs for easy comparison.
Each formula uses different coefficients for men and women.
Results recalculate automatically as you type your height — no button click required.
No frame-size (small/medium/large) adjustment or wrist-circumference input for the Hamwi formula — all four formulas use only height and gender.
Understanding your health numbers is the foundation of informed wellness decisions. The Ideal Weight Calculator uses clinically established formulas to provide science-backed estimates.
Calculate your ideal body weight range using Devine, Hamwi, Robinson, and Miller formulas. See range across multiple methods — free online tool. Results are immediate — no waiting, no loading screens, no account required.
Who uses the Ideal Weight Calculator?
- People setting realistic weight goals with context from multiple medical formulas.
- Healthcare students learning clinical weight estimation methods for dosing calculations.
- Fitness beginners getting a starting reference range before working with a trainer.
Common uses and search terms
The Ideal Weight Calculator is frequently used for: ideal weight, healthy weight, target weight. Whether you need a quick result or are working through a longer project, the tool handles all common variations without any configuration.
Why use Allio Tools's Ideal Weight Calculator?
All calculations run locally. No personal health data is ever transmitted or stored anywhere. The tool is completely free with no usage limits, no premium tiers, and no account required. Available in 11 languages and optimised for all screen sizes, the Ideal Weight Calculator works on desktop, tablet, and mobile with no app download needed.
See also:BMI Calculator · TDEE Calculator · Calorie Calculator
How the Ideal Weight Calculator works
Enter your height in centimeters or inches, and select your gender (the formulas use different constants for men and women).
Results update automatically, showing ideal weight estimates in kg and lbs from four different clinical formulas: Devine, Robinson, Miller, and Hamwi.
Compare the range across all four formulas — they typically differ by a few kilograms from each other.
Tips & tricks
- There's no wrist-circumference or frame-size input — all four formulas (including Hamwi) use only height and gender, unlike some clinical references that adjust Hamwi for small/medium/large frames.
- Results update live as you type your height or change gender — no separate Calculate button click is needed.
- The four formulas typically differ by a few kilograms from each other; treat the spread as a range rather than looking for one "correct" number.
Frequently Asked Questions
Which ideal weight formula is most accurate?
There is no single most accurate formula. Devine, Hamwi, Robinson, and Miller formulas each produce slightly different results. The true "ideal" weight depends on body composition, muscle mass, age, and individual health factors beyond any formula.
Is ideal body weight the same as healthy BMI weight?
No. Ideal body weight formulas use height and sex only. Healthy BMI weight (18.5–24.9) also varies by height. These are rough clinical estimates used in drug dosing, not personalized targets. A healthy weight is individual.
Is BMI a good measure of healthy weight?
BMI has significant limitations — it doesn't distinguish muscle from fat, so athletes with high muscle mass are often incorrectly classified as overweight. It's a population-level screening tool, not an individual health assessment. Body fat % is more meaningful.
What if I'm significantly above or below the ideal weight range?
Consult a healthcare provider before setting weight goals. The formulas are general guidelines. Factors like age, medical history, and body composition make individual targets complex — a registered dietitian can provide personalized guidance.
Does this calculator adjust the Hamwi formula for body frame size (small/medium/large)?
No — there's no frame-size input or wrist-circumference measurement in this tool. All four formulas, including Hamwi, use only height and gender; frame-size adjustments some clinical references add to Hamwi aren't implemented here.
Is my data safe when using the Ideal Weight Calculator?
Completely safe. The Ideal Weight Calculator processes everything locally in your browser. No input data, results, or usage information is ever transmitted to or stored on any server.
How accurate are the Ideal Weight Calculator calculations?
The Ideal Weight Calculator uses clinically validated formulas such as the Mifflin–St Jeor or Harris–Benedict equations where applicable. Results are population-based estimates and can differ from measured values by 10–20% for individuals with atypical body composition. See our <a href="/methodology/">Methodology page</a> for full formula sources and references. Consult a qualified healthcare professional before making medical or dietary decisions.
Which formula does the Ideal Weight Calculator use?
The Ideal Weight Calculator uses an established, peer-reviewed formula endorsed by leading health organisations such as the WHO, CDC, or NIH where applicable. The specific formula is chosen for its validated accuracy across diverse adult populations under normal conditions.
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