Ideal Weight Calculator

Find your ideal weight range using 5 medical formulas with frame size adjustment.

ft
in
Ideal Weight Range
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Across all 5 formulas
Formulalbskg
Devine (1974)——
Robinson (1983)——
Miller (1983)——
Hamwi (1964)——
BMI-based (BMI 22)——
BMI-Based Ideal (BMI 22)
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Mid-range healthy weight
Healthy BMI Range (18.5–24.9)
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Your healthy weight range

How to Use This Ideal Weight Calculator

  1. Select your gender — the formulas differ for males and females, so this is required for accurate results.
  2. Enter your height — switch between imperial (feet and inches) and metric (centimeters) using the toggle.
  3. Choose your frame size — small, medium, or large. If you are unsure, wrap your thumb and middle finger around your wrist: overlapping means small frame, just touching means medium, and a gap means large.
  4. Read the results — the table shows all five formulas with frame size applied. The range at the top shows the minimum and maximum across all formulas.

The Five Ideal Weight Formulas

Medical professionals and researchers have developed several formulas for estimating ideal body weight over the decades. Each was created for a specific clinical purpose and uses height and gender as the primary inputs.

Devine Formula (1974)

Originally developed by Dr. B.J. Devine for drug dosing calculations, this is one of the most cited formulas in clinical medicine. It is calculated as:

Male: 50 + 2.3 × (height in inches − 60)
Female: 45.5 + 2.3 × (height in inches − 60)

Robinson Formula (1983)

Published by Robinson et al., this formula was developed to provide an alternative to Devine with slightly different constants based on updated population data:

Male: 52 + 1.9 × (height in inches − 60)
Female: 49 + 1.7 × (height in inches − 60)

Miller Formula (1983)

The Miller formula tends to produce slightly higher estimates than Robinson and is often used as a comparison point:

Male: 56.2 + 1.41 × (height in inches − 60)
Female: 53.1 + 1.36 × (height in inches − 60)

Hamwi Formula (1964)

One of the oldest formulas, the Hamwi method starts from a base weight at 5 feet and adds weight per inch above that:

Male: 48 + 2.7 × (height in inches − 60)
Female: 45.5 + 2.2 × (height in inches − 60)

BMI-Based Ideal (BMI = 22)

This approach calculates the weight at which your BMI equals 22, which sits comfortably in the middle of the healthy BMI range (18.5–24.9). Many nutrition and health guidelines use BMI 22 as the reference midpoint for a healthy weight:

Ideal weight (kg) = 22 × height (m)²

Frame Size Adjustment

All five formulas assume a medium frame. For small frames, the calculator subtracts 10% from the result. For large frames, it adds 10%. This accounts for the fact that larger-boned individuals naturally weigh more at the same height without having excess fat.

Limitations of Ideal Weight Formulas

Ideal weight formulas are useful reference tools but they have real limitations. They do not account for muscle mass — a highly muscular person may weigh significantly more than the formula suggests while having very low body fat. They also ignore age, with older adults naturally losing muscle and gaining fat even at the same weight. Ethnicity differences in body composition mean that BMI and ideal weight cut-offs may not apply equally across all populations. Finally, these formulas do not consider fitness level, medical conditions, or hormonal factors. Always treat these results as a starting point for conversation with your doctor, not as a prescription for your exact target weight.

Frequently Asked Questions

No single formula is universally most accurate, as ideal weight depends on individual factors like muscle mass, bone density, and body composition. The Devine formula (1974) is widely used in clinical settings for drug dosing. The BMI-based range (18.5–24.9) is considered the most evidence-backed population standard. Comparing all five formulas gives the best overall picture of your healthy weight range.
Frame size refers to the size of your bone structure relative to your height. People with a larger frame have heavier bones and can carry more weight while still being healthy. A common adjustment is ±10% from the medium-frame ideal weight: small frame subtracts 10%, large frame adds 10%. Frame size can be estimated by wrapping your thumb and middle finger around your wrist — overlapping fingers indicate small frame, touching indicates medium, and a gap indicates large.
A healthy BMI is 18.5 to 24.9. In weight terms, this depends on your height. For a 5'9" person, the healthy weight range is approximately 125–168 lbs (57–76 kg). The calculator shows your specific healthy weight range based on your height using BMI 18.5 as the lower bound and BMI 24.9 as the upper bound.
Ideal weight formulas estimate a target based on height and gender, often representing a mid-range BMI (around 22). Healthy weight is a broader range based on BMI 18.5–24.9. Your ideal weight per the formulas is typically near the middle of the healthy BMI range. The two concepts are related but not identical — healthy weight gives a range while ideal weight gives a specific target.
Use ideal weight as a general reference, not a strict target. If your current weight falls within the range shown by multiple formulas, you are likely at a healthy weight. If you are well above the range, gradual weight loss through diet and exercise is beneficial. Always consult a healthcare provider before starting any weight management program, as individual health needs vary significantly.