Ideal Weight Calculator
Calculate your ideal body weight based on height, gender, and frame size. Compare results from 6 medical formulas including Devine, Robinson, and Hamwi with Imperial/Metric unit toggle.
Ideal Weight Calculator
Enter your height and gender
to calculate ideal weight
What is the Ideal Weight Calculator?
The Ideal Weight Calculator is a tool that calculates a healthy weight range based on your height and gender. You can compare six scientific formulas at onceโDevine, Robinson, Miller, Hamwi, Broca, and Petersonโto help set a target weight that’s right for you.
With frame size (small/medium/large) adjustment and Adjusted Body Weight calculation for obese patients, it provides more accurate personalized results. All calculations are performed only in your browser, and no information is stored on any server.
When to Use This Tool
- Setting Diet Goals โ When you need scientific standards for weight loss targets
- Pre-checkup Self-assessment โ To check your ideal weight range before a health checkup
- Exercise Planning โ When setting target weight for strength training or cardio
- Nutrition Consultation Prep โ To understand baseline data before consulting a nutritionist or trainer
- Frame-specific Analysis โ When you need precise target weight considering your frame (bone structure)
- Formula Comparison โ When you want to compare results from multiple ideal weight formulas at a glance
Key Features
- 6 Formulas Calculated at Once โ Compare Devine, Robinson, Miller, Hamwi, Broca, and Peterson formulas simultaneously.
- Frame Size Adjustment โ Auto-detect frame size from wrist circumference and apply small (-10%) or large (+10%) adjustments.
- Adjusted Weight Calculation โ Automatically calculates adjusted body weight used for drug dosing when current weight exceeds 120% of ideal weight.
- BMI Healthy Weight Range โ Shows healthy weight range based on BMI 18.5โ24.9.
- Unit Toggle โ Switch between Metric (cm/kg) and Imperial (ft/in/lbs) units.
- Complete Privacy Protection โ All data is processed only in your browser and never stored on any server.
How to Use
- Select Units โ Choose Metric (cm/kg) or Imperial (ft/in/lbs) based on your preference.
- Enter Height โ Enter your height in your selected unit system.
- Select Gender โ Choose Male or Female. Formulas differ by gender.
- Select Frame Size (Optional) โ Choose small/medium/large, or enter wrist circumference for auto-detection.
- Enter Current Weight (Optional) โ Enter if you need adjusted weight calculation.
- View Results โ Check ideal weights from 6 different formulas and recommended range.
Ideal Weight Formula Details
Devine Formula (1974) โ Medical Standard
The most widely used formula, it’s the standard for drug dosage calculations including levothyroxine and immunoglobulin.
- Male: 50.0 + 2.3 ร (height in inches – 60) kg
- Female: 45.5 + 2.3 ร (height in inches – 60) kg
Robinson Formula (1983) โ Modern Optimized
A modified version of Devine, research suggests it’s more suitable for modern populations.
- Male: 52 + 1.9 ร (height in inches – 60) kg
- Female: 49 + 1.7 ร (height in inches – 60) kg
Miller Formula (1983)
Developed based on the 1983 Metropolitan Life Insurance tables.
- Male: 56.2 + 1.41 ร (height in inches – 60) kg
- Female: 53.1 + 1.36 ร (height in inches – 60) kg
Hamwi Formula (1964) โ Nutrition Standard
Commonly used by nutritionists and dietitians.
- Male: 48.0 + 2.7 ร (height in inches – 60) kg
- Female: 45.5 + 2.2 ร (height in inches – 60) kg
Broca Index (1871) โ Simplest Formula
The oldest formula with 150 years of history, simple but still valid.
- Base: height(cm) – 100 (coefficient varies by height: 100/105/110)
- Male: base ร 0.95
- Female: base ร 0.90
Peterson Universal Formula (2016) โ Latest Research
The latest BMI-linked formula boasting an average error of 0.5โ0.7%.
- Formula: 2.2 ร target BMI + 3.5 ร target BMI ร (height in m – 1.5)
- Male target BMI: 22, Female target BMI: 21
Frame Size Criteria
Frame size is determined by wrist circumference. A ยฑ10% adjustment is applied to ideal weight based on frame.
Male Criteria
- Small: Wrist under 6.5″ (16.5cm)
- Medium: Wrist 6.5″โ7.5″ (16.5โ19cm)
- Large: Wrist over 7.5″ (19cm)
Female Criteria
- Small: Wrist under 6.0″ (15.2cm)
- Medium: Wrist 6.0″โ6.5″ (15.2โ16.5cm)
- Large: Wrist over 6.5″ (16.5cm)
Frequently Asked Questions
Which formula is most accurate?
The Devine formula is most widely validated in medical settings and used as standard for drug dosage calculations. However, some research suggests the Robinson formula may be more suitable for modern populations. Consider using the average or range from multiple formulas.
Why is frame adjustment necessary?
Since people have different bone structures, those with larger frames and thicker bones have different ideal weights than those with smaller frames, even at the same height. Frame adjustment reflects approximately a 10% difference.
When is Adjusted Body Weight used?
For obese patients whose current weight exceeds 120% of ideal body weight, adjusted body weight is used when calculating drug dosages or nutritional requirements. The formula is IBW + 0.4 ร (actual weight – IBW).
How do I measure wrist circumference?
Measure around the narrowest part of your wrist (just below the wrist bone) with a tape measure. The tape should touch the skin but not be too tight.
Is my information saved?
No, all calculations are performed only in your browser, and no information is sent to or stored on any server. Refreshing the page will reset all entered values.
Why do different formulas give different results?
Each formula was developed at different times, for different study populations, and for different purposes, resulting in varying results. Differences between formulas can be up to 14% for males and 19% for females. It’s recommended to reference the average or range from multiple formulas.
Does this apply to muscular athletes?
Ideal weight formulas are developed for average individuals and may be inappropriate for highly muscular athletes or bodybuilders. In such cases, consider using a body fat calculator or consult a professional.