About the Ideal Weight Calculator
Ideal Weight Calculator helps estimate the key numbers involved in fitness decisions. It is designed for quick scenario comparison: enter a realistic set of values, calculate the result, then change one assumption at a time to see what has the greatest effect. Unlike a static table, the result responds to your inputs and keeps the calculation in your browser. Health and fitness results are population-based estimates. They can support a conversation or planning process, but they do not determine an individual diagnosis, treatment, or safe activity level.
How to use this calculator
Enter values that match your situation and select Calculate result. Review the main result and its supporting figures, then change one input at a time to compare scenarios. Results are rounded for readability while the calculation retains additional precision internally.
Information you will need
- Sex
- Height
- Frame size
How the calculation works
Ideal body weight using Devine, Robinson, Miller, and Hamwi formulas. Read the primary result together with the supporting values rather than focusing on one number alone. A useful estimate should make its assumptions visible. If the answer looks surprising, verify the unit, rate, time period, and whether the entered value is gross or net. Run a conservative and an optimistic scenario to understand the range of possible outcomes.
Formula or method
Devine: 50 + 2.3(inches over 5ft) for men, 45.5 + 2.3 for women.
Worked example
Multiple formulas averaged for a range.
The example is illustrative rather than a recommendation. Use your own verified values and keep all monetary or measurement units consistent. When comparing alternatives, save or note each result so the assumptions do not become mixed.
How to interpret the result
The primary output answers the main question posed by the ideal weight calculator, while the additional cards provide context. A result with many decimal places is not necessarily more certain. The displayed precision makes comparison easier, but uncertainty in the inputs can be larger than the rounding difference.
Look for trends and ranges instead of treating a single estimate as a pass or fail result. If the output conflicts with symptoms, professional advice, or a direct measurement, rely on appropriate professional assessment.
Limitations and important notes
The ideal weight calculator cannot account for every factor that affects an individual result. Measurement technique, hydration, body composition, medication, pregnancy, illness, training status, and normal biological variation may matter. Do not use an estimate to diagnose a condition, select medication dosage, decide whether to drive, or ignore symptoms. A qualified professional can interpret measurements in the context of history and appropriate testing.
Frequently asked questions
What is my ideal body weight?
This calculator averages four widely recognized formulas (Devine, Robinson, Miller, and Hamwi) to estimate your ideal weight. The result is a broad reference, not a mandatory target. Each formula was developed for different purposes — Devine for medication dosing, others for insurance tables. Your doctor can help set a healthy weight goal based on your individual composition and health.
Why are there four different formulas?
Different researchers developed different formulas at different times for different populations. Devine (1974) is most widely used for medication dosing. Robinson (1983) and Miller (1983) were based on insurance data. Hamwi (1964) was originally for pharmaceutical dosing. By averaging all four, you get a more robust consensus estimate that accounts for the variation between methods.
What does frame size do?
Frame size adjusts the average estimate by ±10%. Small frame (narrow wrists, delicate build) shifts the estimate down 10%, large frame (wide wrists, broad build) shifts it up 10%. Medium frame uses the unadjusted average. Frame size is a rough classification — if unsure, medium is the safest choice.
What is the difference between ideal weight and healthy weight range?
An ideal weight is a single number produced by averaging four formulas, while a healthy weight range is a band of acceptable weights — usually defined by a BMI of 18.5–24.9. The range is more practical for goal setting because it allows for individual variation in body type and composition.
Can I be healthy at a weight above the formula's ideal?
Yes. Formula-based ideals assume average body composition and frame, so a muscular or large-framed person can be perfectly healthy above the number. What matters more is body fat distribution and health markers like blood pressure and blood sugar. Use the ideal as context, and let your doctor help you decide what weight is genuinely appropriate for you.
How is the Hamwi formula different from Devine?
Both are sex-specific equations, but they use different baselines. Hamwi gives men 48 kg for the first 5 feet plus 2.7 kg per inch, while Devine gives 50 kg plus 2.3 kg per inch. For a 5'10" man, Hamwi gives about 73.5 kg while Devine gives about 71.5 kg. Neither is more "correct" — that is why this calculator averages all four.