Ideal Weight Calculator — What Should You Actually Weigh?

"What should I weigh?" sounds like a simple question. The honest answer is that it depends — on your height, frame size, age, and what you're optimizing for. There's no single magic number, but there is a useful range, and that's what this calculator gives you.

Try the ideal weight calculator on CalcHub to see your range using multiple formulas.

The Formulas Behind the Calculator

Several medical formulas have been developed over the decades to estimate ideal body weight. CalcHub runs four of the most widely referenced:

Formula	Men	Women
Devine (1974)	50 kg + 2.3 kg per inch over 5 ft	45.5 kg + 2.3 kg per inch over 5 ft
Robinson (1983)	52 kg + 1.9 kg per inch over 5 ft	49 kg + 1.7 kg per inch over 5 ft
Miller (1983)	56.2 kg + 1.41 kg per inch over 5 ft	53.1 kg + 1.36 kg per inch over 5 ft
Hamwi (1964)	48 kg + 2.7 kg per inch over 5 ft	45.5 kg + 2.2 kg per inch over 5 ft

These formulas were originally developed for clinical dosing calculations (figuring out medication doses by estimated lean body mass), not fitness goals. Still, they're useful reference points and the range they collectively produce is reasonably practical.

Why You Get a Range, Not a Number

Each formula produces a slightly different number, and that spread reflects something real: ideal body weight is genuinely a range, not a precise target. A person who is 5'9" might have an ideal weight anywhere from 140 to 175 lbs depending on:

• Frame size — people with larger bone structures naturally weigh more even at the same body fat percentage
• Muscle mass — trained individuals carry more weight that is healthy and beneficial
• Age — slight weight gain in older adults is often associated with better outcomes, not worse

Chasing a specific number can lead you somewhere worse than where you started. The range is the goal.

Determining Your Frame Size

Wrap your thumb and index finger around your wrist:

• Fingers overlap → small frame


• Fingers just touch → medium frame


• Gap between fingers → large frame

This is a rough method but gives useful context. Small-frame individuals should target the lower end of their ideal weight range; large-frame people can reasonably target the upper end.

What If You're Currently Outside the Range?

The range is a target for direction, not a judgment. If you're above your ideal weight range, a modest calorie deficit and resistance training over several months will move you there gradually. If you're below (and not intentionally so), the same principles apply in the other direction.

Don't try to hit the range in 30 days. Body weight changes of more than 1–2 lbs per week come mostly from water and muscle, not fat, and the loss doesn't stick.

These formulas are estimates based on population averages. For personalized weight goals, speak with your doctor or a registered dietitian.

Is ideal weight the same as healthy weight?

They overlap but aren't identical. "Healthy weight" is often defined by a BMI between 18.5 and 24.9. Ideal weight formulas tend to produce targets that fall within that BMI range for most heights, but not always — particularly for taller individuals where the formulas can undershoot.

Should athletes target ideal weight?

Not necessarily. Ideal weight formulas don't account for muscle mass. A competitive athlete may be well above the "ideal weight" range while being in peak physical condition with low body fat. Body fat percentage is a more meaningful metric for trained individuals.

What about ideal weight for children?

Pediatric ideal weight uses growth charts specific to age and sex — standard adult formulas don't apply to anyone under 18. Your pediatrician's growth chart is the right reference.

Related Calculators

• BMI Calculator — see how your current weight compares to population norms
• Body Fat Percentage Calculator — track composition, not just weight
• Calorie Calculator — build a plan to reach your target weight