Complete Ideal Weight Calculator Guide 2025
Achieving and maintaining a healthy weight is a cornerstone of long-term health. An Ideal Weight Calculator provides a scientific baseline for your fitness goals by analyzing your height and biological sex to estimate a weight range associated with lower health risk.
Our Ideal Weight Calculator uses two well-known clinical formulas — the Devine and Robinson formulas — along with a healthy BMI-based weight range for reference. It's completely free, works instantly, and requires no sign-up.
Health Insight:
Ideal weight is not a "one size fits all" number. Bone density, muscle mass, and individual body composition all influence what a healthy weight looks like for any given person. Treat the result as a reference range, not a strict target.
The Two Formulas This Calculator Uses
1. The Devine Formula (1974)
Originally developed to help estimate medication dosing based on body size, the Devine formula has since become one of the most widely referenced methods for estimating ideal body weight in clinical settings.
2. The Robinson Formula (1983)
A later refinement building on the same underlying approach as Devine, often cited in nutritional and clinical literature as a comparable alternative estimate.
Note on the "Age" Field:
This calculator includes an optional Age input, but the current calculation uses only your height and biological sex — age does not change the result. It's included for your own reference and possible future use.
The Formulas, In Detail
Devine — Men: 50 kg + 2.3 kg for every inch over 5 feet
Devine — Women: 45.5 kg + 2.3 kg for every inch over 5 feet
Robinson — Men: 52 kg + 1.9 kg for every inch over 5 feet
Robinson — Women: 49 kg + 1.7 kg for every inch over 5 feet
The calculator also shows a Healthy BMI Weight Range for your height, calculated using the WHO's standard BMI thresholds of 18.5 (lower bound) and 24.9 (upper bound).
How to Use This Calculator:
- Select Biological Sex: Male or Female — this changes the constants used in both formulas.
- Enter Height in Centimeters.
- View Results: See your Devine estimate, Robinson estimate, and healthy BMI weight range side by side.
Units Note:
This calculator currently accepts height in centimeters only and displays results in kilograms. If you know your height in feet and inches, convert it to cm first (multiply feet by 30.48 and add inches × 2.54).
Longevity Tip:
Remember that muscle is denser than fat. If you strength train regularly, you might weigh more than these formulas suggest while still being in excellent health — body composition matters as much as the number on the scale.
Reference Table: Estimated Ideal Weight by Height
| Height |
Devine (Men) |
Robinson (Men) |
Devine (Women) |
Robinson (Women) |
| 5'4" (163 cm) | 59.6 kg | 59.9 kg | 55.1 kg | 56.1 kg |
| 5'8" (173 cm) | 68.7 kg | 67.4 kg | 64.2 kg | 62.8 kg |
| 6'0" (183 cm) | 77.7 kg | 74.9 kg | 73.2 kg | 69.5 kg |
Values calculated directly from this calculator's formulas.
Limitations of Ideal Weight Formulas
- Not designed for children, pregnant women, or elite athletes with unusually high muscle mass.
- Doesn't account for body composition — two people at the same "ideal weight" can have very different amounts of muscle versus fat.
- Population averages, not individual prescriptions — genetics and frame size cause natural variation.
Medical Disclaimer:
The information provided by this calculator is for educational purposes only and should not be considered medical advice. Always consult with a qualified healthcare provider or registered dietitian before making major changes to your diet or exercise routine.
Conclusion
Ideal weight formulas give you a useful reference range based on your height, but they work best as one data point alongside other measures of health like body composition, fitness level, and how you actually feel. Use the calculator above to get your estimate, and discuss any specific weight goals with a healthcare professional.