Ideal Weight Calculator
Find your ideal body weight using Hamwi, Devine, Robinson and Miller formulas plus a healthy BMI range. Free for men and women.
Hamwi (1964)
66.7 kg
Devine (1974)
65.9 kg
Robinson (1983)
65.2 kg
Miller (1983)
66 kg
Healthy BMI range
53.5 – 72.3 kg
WHO BMI 18.5–25
Ideal body weight (IBW) formulas were created for medical dosage, not looks. They ignore body fat and muscle, so a muscular person can be “overweight” and perfectly healthy. These are reference points, not targets.
How it works
Devine male: 50 kg + 2.3 kg/inch over 5 ft. Devine female: 45.5 kg + 2.3 kg/inch over 5 ft. Healthy BMI 18.5–25.
Example: 170 cm (5 ft 7 in) male → Devine ≈ 66.1 kg.
Last updated: June 2026
How this calculator is verified
Checked by True Calculator automated test suite on
- Formula verified against a published worked example in the automated test suite
- Edge cases (zero, negative, boundary and unit-mismatch inputs) covered by unit tests
The full verification method is on our how we verify page. Found an error? Tell us and we will re-check it.
When to Use This Calculator
Use the ideal weight calculator when you want a sensible weight range for your height instead of a single target. Doctors and nutritionists in India commonly quote ranges based on healthy BMI, and this tool layers the classic Hamwi, Devine, Robinson and Miller formulas on top, so you can compare how the different methods answer for your body frame. It is useful before a medical check-up, when planning a weight-loss goal that is realistic rather than arbitrary, and when starting a diet where you want the end point defined. The healthy-range view matters most: staying inside it keeps the risk factors for diabetes and blood pressure lower, which is why physicians refer to it during routine consultations. Use the male and female options to get gender-appropriate calculations.
How to Use This Calculator
- Step 1: Choose metric units and enter your height in centimetres.
- Step 2: Select your sex, since the four formulas use different base weights for men and women.
- Step 3: Calculate and read the Hamwi, Devine, Robinson and Miller results in kilograms.
- Step 4: Compare them with the healthy BMI range, which for your height is shown as a minimum and maximum weight.
Worked Example
For a 35-year-old woman who is 160 cm tall, the calculator applies four classic formulas. Hamwi gives about 52 kg, Devine about 52 kg, Robinson about 54 kg and Miller about 57 kg. It also shows the healthy BMI band of 18.5 to 25, which for 1.6 m means roughly 47 to 64 kg. Because the Asia-Pacific BMI cutoffs used in India treat 23 and above as overweight, staying near the lower half of that band is commonly advised. The formulas were developed in different decades, so small differences between them are expected.
Tips and Common Mistakes
- •Tip 1: Use the healthy BMI range as the practical target, since the four formulas are decades-old clinical tools that can disagree by several kilograms.
- •Tip 2: For Indian adults, prefer the lower part of the healthy range, given the Asia-Pacific cutoffs that flag risk from a BMI of 23.
- •Tip 3: If you are muscular, expect the formulas to understate your natural weight, because they were built from general clinical populations.
- ✗Mistake 1: Treating the single formula values as a strict goal; they are estimates, and a range based on BMI is a safer target.
- ✗Mistake 2: Entering height in feet and inches when the field expects centimetres, which shifts every result far from your actual values.
Frequently Asked Questions
What is the ideal weight formula?
For men, Devine: 50 kg + 2.3 kg per inch over 5 feet. For women, Devine: 45.5 kg + 2.3 kg per inch over 5 feet. Hamwi, Robinson and Miller are similar formulas with different base weights — this calculator shows all four.
Is ideal body weight the same as a healthy weight?
Not exactly. IBW formulas were created for medical dosage calculations and ignore body fat, muscle and frame size. The healthy BMI range (18.5–25, or 18.5–23 for Asian cutoffs) is a broader and more useful guide.
Why do the four formulas give different results?
Each formula was derived from different study populations. Devine tends to give the highest values, Robinson the lowest, with Hamwi and Miller in between. Differences are usually a few kilograms.
Can a muscular person be above their ideal weight and still be healthy?
Yes. All these formulas assume average muscle mass. Athletes and bodybuilders can exceed the number while having low body fat — which is why IBW should not be treated as a strict target.
Compare these tools
- BMI Calculator — Calculate your Body Mass Index instantly and see your WHO weight category
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