Knowing your ideal body weight is a helpful starting point for setting realistic fitness and health goals. This calculator estimates a healthy weight range for adult men based on your height, age, and frame size. It combines the classic Devine formula with a modern BMI-based range, giving you both a single target and a broader healthy zone.
Whether you're planning a weight-loss program, tracking muscle gain, or just curious where you stand, this tool offers a quick, evidence-informed reference. Simply enter your height, age, and select your frame size to see your estimated ideal weight, the healthy BMI range, and a personalized breakdown. Use the results as a guide — not a strict prescription — and always consult a healthcare professional for individual advice.
📏 Enter Your Details
How to Use This Tool
Enter your height in centimeters, feet, or inches using the dropdown next to the height field. Then input your age (between 18 and 100) and select your frame size — small, medium, or large. If you're unsure about your frame size, a simple method is to wrap your thumb and middle finger around your opposite wrist: if they just touch, you're medium; if they overlap, you're small; if they don't touch, you're large. Click Calculate Ideal Weight to see your estimated ideal weight, the healthy BMI range for your height, and a step-by-step breakdown of the math. Use the quick-height buttons to instantly fill common values.
Formula Explained
The calculator uses the Devine formula, originally developed for estimating ideal body weight in clinical settings. For men, the formula is:
Ideal weight (kg) = 50 + 2.3 × (height in inches − 60)
This formula assumes a medium frame and a height of 5 feet (60 inches) as the baseline. For every inch above 5 feet, 2.3 kg is added. We then adjust for frame size: subtract 10% for a small frame and add 10% for a large frame. The result is cross-checked against the standard BMI healthy range of 18.5–24.9 kg/m², which is widely used by health organizations. The BMI range is calculated as BMI = weight (kg) / height² (m²), so the healthy weight range is simply 18.5 × height² to 24.9 × height².
Worked Examples
Example 1: A 30-year-old man, 180 cm tall, medium frame.
Height in inches = 180 / 2.54 = 70.87 in. Devine ideal = 50 + 2.3 × (70.87 − 60) = 50 + 2.3 × 10.87 = 75.0 kg. Frame adjustment = 0. Healthy BMI range = 18.5 × (1.8)² = 59.9 kg to 24.9 × (1.8)² = 80.7 kg. So his ideal weight is 75.0 kg, comfortably within the healthy range.
Example 2: A 45-year-old man, 5 ft 8 in (172.7 cm), large frame.
Height in inches = 68. Devine ideal = 50 + 2.3 × (68 − 60) = 50 + 18.4 = 68.4 kg. Large frame adjustment = +10% = +6.8 kg, giving 75.2 kg. Healthy BMI range = 18.5 × (1.727)² = 55.2 kg to 24.9 × (1.727)² = 74.3 kg. His adjusted ideal weight (75.2 kg) is slightly above the BMI range, which is expected for a larger frame.
Tips & Best Practices
- Use this calculator as a reference point, not a strict target. Muscle mass, bone density, and body composition vary widely among individuals.
- For a more complete picture, combine your ideal weight with body fat percentage and waist circumference measurements.
- If you're an athlete or bodybuilder, your ideal weight may be higher due to increased muscle mass — BMI may not be the best metric for you.
- Always consult a healthcare professional before starting any weight-loss or weight-gain program.
Limitations & Precision Notes
The Devine formula was developed for clinical use and may not be accurate for very tall or very short individuals, or for those with extreme muscle mass. Frame size estimation is subjective and can affect the result by up to 10%. The BMI range is a population-level guideline and does not account for body composition. Therefore, treat the output as an estimate with a typical accuracy of ±5–10%.
Frequently Asked Questions
Is the Devine formula the same as the Hamwi formula?
No. The Hamwi formula for men is 48.0 kg + 2.7 kg per inch over 5 feet, which gives slightly different results. The Devine formula is more commonly used in clinical settings and is the basis for many drug dosing calculations.
Why does my ideal weight differ from the BMI range?
Because the Devine formula is a single-point estimate based on height, while the BMI range is a broad interval. Your frame size adjustment can push the estimate outside the BMI range, especially for large or small frames.
Can I use this for women?
This calculator is specifically for men. For women, the Devine formula uses a baseline of 45.5 kg instead of 50 kg. You can find a dedicated women's calculator on our site.
What is the source of the BMI range?
The 18.5–24.9 range is the standard classification from the World Health Organization (WHO) for normal weight in adults. You can read more on the WHO fact sheet.
Additional Resources
For more detailed information on body weight and health, consider these authoritative sources:
- NIH BMI Calculator — official BMI tool from the National Heart, Lung, and Blood Institute.
- CDC Adult BMI Information — explains how BMI is used and its limitations.
- Devine Formula on Wikipedia — background on the formula's origin and usage.
If you're tracking other health metrics, you might also find our Ideal Weight for Women Calculator useful (note: this link is illustrative).