Weight & Height Calculator | Free BMI & Ideal Weight Tool
Find out your ideal weight using four medical formulas (Devine, Miller, Hamwi, Robinson), calculate your BMI (Body Mass Index), and check your Waist-to-Height Ratio — a more accurate health risk indicator. Simple, fast, and 100% free.
📖 Want to understand your results?
Read our complete guide to the Weight & Height Calculator — with real-world examples, expert insights, and pro tips.
— Advertisement —
Below Result
Responsive
Slot: placeholder-calc-bottom-slot
What Is the Ideal Weight for My Height?
Your ideal weight depends on your height, gender, and body frame. Medical professionals use several formulas to estimate ideal body weight (IBW). Our calculator uses four of the most common formulas — Devine, Miller, Hamwi, and Robinson — and takes the average to give you a practical target weight.
In addition to ideal weight, we calculate your BMI (Body Mass Index) and Waist-to-Height Ratio (WtHR) to give you a complete picture of your health. Research shows WtHR is often a better predictor of cardiovascular risk than BMI alone.
BMI Categories
| BMI Range | Category | Health Risk |
|---|---|---|
| < 16.0 | Severely Underweight | High |
| 16.0 – 16.9 | Moderately Underweight | Moderate |
| 17.0 – 18.4 | Mildly Underweight | Low |
| 18.5 – 24.9 | Normal Range ✅ | Low |
| 25.0 – 29.9 | Overweight | Moderate |
| 30.0 – 34.9 | Obese Class I | High |
| 35.0 – 39.9 | Obese Class II | Very High |
| ≥ 40.0 | Obese Class III | Extremely High |
The 4 Ideal Weight Formulas Explained
Originally developed for medication dosing. Most commonly used in hospitals. Men: 50kg + 2.3kg per inch over 5ft. Women: 45.5kg + 2.3kg per inch over 5ft. Typically gives lower estimates.
Updated standard with gentler per-inch increments. Often used in nutritional counseling. Men: 56.2kg + 1.41kg per inch over 5ft. Women: 53.1kg + 1.36kg per inch over 5ft.
Older, stricter formula that tends to give lower ideal weights. Still used in some clinical settings. Men: 48kg + 2.7kg per inch over 5ft. Women: 45.5kg + 2.2kg per inch over 5ft.
Moderate formula that falls between Devine and Miller. Often used as a weight loss goal. Men: 52kg + 1.9kg per inch over 5ft. Women: 49kg + 1.7kg per inch over 5ft.
Why Waist-to-Height Ratio Matters
The Waist-to-Height Ratio (WtHR) is a powerful health screening tool. Research published in the British Medical Journal found that WtHR is a better predictor of heart disease, diabetes, and stroke than BMI. The goal is to keep your waist circumference less than half your height.
For example, a person who is 170cm tall should aim for a waist circumference below 85cm (170 × 0.5). Unlike BMI, WtHR accounts for body fat distribution — abdominal fat (apple-shaped) carries higher health risks than fat stored elsewhere.
Limitations of These Measurements
BMI doesn't distinguish between muscle and fat. Athletes and bodybuilders may have a high BMI but very low body fat. Elderly individuals may have lower muscle mass but a normal BMI. Always use alongside other measurements.
The formulas don't account for body frame size, muscle mass, or ethnicity. They provide estimates based on population averages. Your healthy weight may differ. Consult a doctor for personalized advice.
— Advertisement —
Content Mid
Responsive
Slot: placeholder-in-content-slot
Tips for Healthy Weight Management
- Focus on body composition, not just weight — A healthy weight range with good muscle mass is better than a low weight with low muscle.
- Aim for the healthy BMI range (18.5–24.9) — Use our calculator to find your target range and ideal weight average.
- Track your waist measurement — A WtHR under 0.5 is associated with lower risk of heart disease and type 2 diabetes.
- Make sustainable changes — Aim for 0.5–1kg per week weight change through balanced diet and regular exercise.
- Consider age and gender — Our calculator adjusts ideal weight formulas by gender. As you age, your body composition changes, so regular check-ups matter.
Frequently Asked Questions
How much should I weigh for my height?
There is no single 'ideal' weight. Most medical professionals use a range of formulas. For a 170cm (5 foot 7 inch) person, the healthy BMI range is 53.5–72.0kg. The average ideal weight from 4 common formulas is approximately 65.5kg for men and 60.5kg for women at that height.
What is the most accurate ideal weight formula?
No single formula is perfect for everyone. The Devine formula is most commonly used in clinical settings for medication dosing. The Miller formula is considered more modern and realistic. We recommend using the average of all four as a practical target.
Is BMI still a good measure of health?
BMI is a useful screening tool but has limitations. It doesn't account for muscle mass, bone density, or fat distribution. Athletes may have high BMI but low body fat. Waist-to-Height Ratio (WtHR) is considered a better predictor of health risks.
What is the Waist-to-Height Ratio and why is it important?
Waist-to-Height Ratio (WtHR) compares your waist circumference to your height. A ratio of 0.5 or less is considered healthy. Research shows WtHR is a better predictor of heart disease, diabetes, and stroke than BMI.
Do men and women have different ideal weights?
Yes. Men generally have higher ideal weights than women at the same height because men have more muscle mass and denser bones. All four formulas used in our calculator have different baselines and per-inch increments for men and women.
How do I measure my waist correctly?
Use a flexible tape measure. Stand up straight and breathe normally. Measure at the narrowest point of your waist, usually just above your belly button. Make sure the tape fits snugly but doesn't compress your skin.
Weight & Height Calculator Pros & Cons
Pros
- ✅ BMI, ideal weight & WtHR in one tool
- ✅ 4 medical formulas averaged
- ✅ Free forever — no subscriptions
- ✅ Works offline after page load
- ✅ No sign-up or email required
Cons
- ✗ No Excel/CSV export option
- ✗ No dedicated mobile app
Reviewed by Dr. Sarah Mitchell
Health & Nutrition SpecialistRegistered dietitian and exercise physiologist with 12+ years of clinical experience.
Footer Banner
Responsive
Slot: placeholder-footer-slot