Most people who search "ideal weight for my height" land on a single number pulled from a random chart, with no idea where it came from. That number usually traces back to one of a handful of formulas developed decades ago — often for reasons that have nothing to do with fitness.
The problem with "ideal weight" charts
Ideal Body Weight (IBW) formulas aren't fitness inventions. The most widely used one, the Devine formula, was published in 1974 in a paper about calculating drug doses — specifically creatinine clearance — not about what a healthy person should weigh. Clinicians needed a quick way to estimate lean body size without being thrown off by excess fat mass, so they built a formula: a base weight for someone 5 feet tall, plus a fixed increment per inch above that.
Three other formulas followed, each derived from different population data:
- Devine (1974) — the clinical standard, still used in most EHR systems and drug-dosing calculations
- Robinson (1983) — a revision of Devine intended to better fit population data, generally lower for tall men
- Miller (1983) — higher base weight, smaller per-inch increment; used in some respiratory therapy protocols
- Hamwi (1964) — the oldest, a simple rule of thumb (106 lbs for men at 5', +6 lbs/inch) designed to be usable without a calculator
Each gives a different answer for the same height and sex, sometimes by several kilograms. Relying on just one is misleading — which is the whole reason we built a calculator that runs all four side by side instead of picking a favorite.
What the calculator does
The Ideal Weight Calculator takes your height and sex and returns:
- All four formula results (Devine, Robinson, Miller, Hamwi) in both kg and lbs
- The average of the four — a more stable estimate than any single formula
- The WHO BMI-based healthy weight range (BMI 18.5–24.9) for your height, which is a range, not a single target
- If you enter your current weight, your current BMI and how far you sit from the formula average
Everything runs client-side — no data leaves your browser, no signup, no limits.
Why the range matters more than the number
Here's the part most ideal-weight tools skip: the four-formula average usually lands in the lower-middle of the BMI healthy range, not the middle. For a 175 cm man, the formula average comes out around 70 kg, while the full healthy BMI range extends up to about 76 kg. That means someone at the top of a healthy BMI is technically "above" every IBW formula while still being in a clinically fine range.
This matters most for people the formulas were never built for: muscular individuals. A 5'10" powerlifter at 10% body fat can weigh 95 kg — well above the Devine estimate of 73 kg for that height — while being in significantly better health than someone who actually weighs 73 kg with a higher body fat percentage. IBW formulas only look at height and sex; they have no idea whether that weight is muscle or fat. If that sounds like you, a body fat percentage estimate is a far more useful number than any IBW formula.
Who this is actually useful for
- Anyone who wants a sanity-check target without picking a random formula off a chart
- People tracking weight change who want to know if they're moving toward or away from a healthy range
- Students or clinicians who want to compare how the four classic formulas diverge at different heights
Try it free
No signup, no account, results calculated instantly in your browser: https://nutilz.com/ideal-weight-calculator
Free tools shouldn't require you to hand over an email address just to do arithmetic. That's the whole premise behind Nutilz — calculators and utilities that just work, with no paywall and no account wall.
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