Finding your healthy weight is not always simple, but the Ideal Body Weight Calculator makes it easier than ever. This free online tool helps you quickly calculate your ideal body weight (IBW) based on your height, gender, age, and body frame size.
Whether you are starting a fitness journey, monitoring your health, or just curious about where you stand, our calculator provides reliable results using proven medical formulas such as Devine, Hamwi, Robinson, and Miller equations.
Unlike basic BMI charts, this calculator offers a more personalized approach, making it useful for both men and women, athletes, and even pediatric cases. By using this tool, you can not only calculate your ideal body weight but also compare it with your current weight, track your BMI, and understand the adjustments needed for better health.
Why an Ideal Body Weight Calculator Matters
When it comes to health, fitness, or medical treatment, knowing your ideal body weight (IBW) is more than just a number. It’s an important guideline used by doctors, dietitians, and fitness coaches to determine if your current weight is within a healthy range. Our free Ideal Body Weight Calculator helps you estimate the right weight for your body based on widely accepted formulas like Devine, Robinson, Miller, Hamwi, and Lorentz.
Whether you want to calculate ideal body weight for fitness goals, medical dosing, or simply to improve your health, this tool provides instant results along with a helpful height-to-weight reference table.
What Is an Ideal Body Weight Calculator?
An ideal body weight calculator is a tool designed to determine the weight range that is considered healthy for a person based on their height, gender, and sometimes age or body frame. Unlike the Body Mass Index (BMI), which uses weight and height to calculate categories like underweight or obese, IBW focuses on formulas created by researchers for clinical and nutritional use.
In hospitals, the IBW is often used to:
- Adjust drug dosages
- Calculate ventilation tidal volumes
- Estimate nutritional needs
- Assess overall health status
How to Calculate Ideal Body Weight
There are multiple formulas for calculating ideal body weight, and each has slightly different outcomes. Our calculator uses the most popular ones to give you a well-rounded result.
1. Devine Formula (1974)
- Men: 50 + 2.3 × (height in inches – 60)
- Women: 45.5 + 2.3 × (height in inches – 60)
👉 Most commonly used in clinical medicine for drug dosage and ventilator settings.
2. Robinson Formula (1983)
- Men: 52 + 1.9 × (height in inches – 60)
- Women: 49 + 1.7 × (height in inches – 60)
👉 Provides slightly lower values than Devine, often used in nutritional assessments.
3. Miller Formula (1983)
- Men: 56.2 + 1.41 × (height in inches – 60)
- Women: 53.1 + 1.36 × (height in inches – 60)
👉 A balanced formula that accounts for differences in body composition.
4. Hamwi Formula (1964)
- Men: 48 + 2.7 × (height in inches – 60)
- Women: 45.5 + 2.2 × (height in inches – 60)
👉 Widely used in diet planning and nutrition.
5. Lorentz Formula
- Men: Height (cm) – 100 – [(Height – 150) ÷ 4]
- Women: Height (cm) – 100 – [(Height – 150) ÷ 2]
👉 Simple formula, mainly used in Europe.
Why Are There Different Ideal Body Weight Formulas?
The reason multiple formulas exist is because body composition varies across genders, ethnicities, and populations. No single formula is perfect for everyone, which is why our IBW calculator shows results from all methods, giving you a comprehensive view.
BMI vs Ideal Body Weight Calculation
Many people confuse BMI (Body Mass Index) with IBW (Ideal Body Weight).
- BMI = weight ÷ (height in meters²) → categorizes you as underweight, normal, overweight, or obese.
- IBW = best weight range for health and clinical calculations, based only on height and gender.
👉 Example:
- A male 175 cm tall might have an IBW around 67–70 kg depending on the formula.
- His BMI at 75 kg would be 24.5 (still within the normal range).
Both values are important, but IBW is more formula-based and often used in medicine, while BMI is for population-level health assessment.
How Do You Calculate Your Ideal Body Weight?
Using our free body ideal weight calculator:
- Select your gender.
- Enter your height in centimeters or inches.
- Enter your actual weight (for BMI and ABW).
- Hit Calculate.
- Get results for:
- Devine, Robinson, Miller, Hamwi, Lorentz
- Adjusted Body Weight (ABW)
- Lean Body Weight (LBW)
- BMI with category (underweight, normal, overweight, obese).
Adjusted Ideal Body Weight Calculator (ABW)
Sometimes, especially in obesity or clinical cases, the Adjusted Body Weight (ABW) formula is used:
ABW = IBW + 0.4 × (Actual Weight – IBW)
This is important for patients who are overweight, as medication doses cannot be based only on actual weight.
👉 Our adjusted ideal body weight calculator automatically applies this formula when you enter your actual weight.
Lean Body Weight (LBW)
LBW refers to the weight of everything in your body except fat – muscles, bones, water, and organs.
Our tool uses the Janmahasatian formula to estimate LBW, which is especially useful in pharmacology and fitness planning.
Pediatric Ideal Body Weight Calculation
For children, pediatric ideal body weight calculators are used with adjusted equations. While adult formulas like Devine don’t directly apply, healthcare professionals use age, gender, and height-based growth charts to estimate IBW.
👉 Parents and pediatricians use these values to monitor growth and detect malnutrition or obesity early.
Ideal Body Weight for Men vs Women
Men and women have different IBW formulas because of different muscle mass and fat distribution.
- Ideal body weight calculator for men typically shows slightly higher numbers.
- Ideal body weight calculator female results are lower due to natural body composition.
For example, at 170 cm:
- Male IBW (Devine) ≈ 66 kg
- Female IBW (Devine) ≈ 61 kg
Practical Uses of an Ideal Body Weight Calculator
An IBW calculator isn’t just for curiosity – it has real-world applications:
- Medical dosing (especially in anesthesia and chemotherapy)
- Ventilator settings (tidal volume based on IBW, not actual weight)
- Nutrition planning (setting calorie goals)
- Fitness & bodybuilding (deciding target weight for muscle gain or fat loss)
- Research & clinical trials
Limitations of Ideal Body Weight Calculations
While useful, IBW formulas do not account for:
- Body fat percentage
- Muscle mass differences
- Athletic build vs sedentary lifestyle
- Age-related changes
👉 That’s why you should use IBW along with BMI, body fat %, and waist-to-hip ratio for a complete health picture.
Example Calculations
Let’s take a male, 180 cm tall, 80 kg weight:
- Devine IBW = 72.7 kg
- Robinson IBW = 73.6 kg
- Hamwi IBW = 75.1 kg
- BMI = 24.7 (Normal)
- ABW = 74.6 kg
- LBW = 65.2 kg
This shows that while his actual weight is slightly above IBW, his BMI is still in the normal range.
How to Use the Height-to-Weight Chart
Our tool also generates a height-to-weight reference table from 150 cm to 200 cm, showing the ideal body weight range (±10%).
This helps you see whether your weight is close to the healthy target.
Related Calculators
Along with our ideal body weight calculation tool, you may also find these useful:
- BMI Calculator | Reverse BMI Calculator
- Body Fat Calculator
- Lean Body Mass Calculator
- Calorie Needs Calculator
Frequently Asked Questions (FAQs)
1. What is the best formula for calculating ideal body weight?
👉 The Devine formula is most widely used in medicine, but Robinson and Miller are also popular.
2. How do I calculate my ideal body weight at home?
👉 You can use our free ideal body weight calculator online by entering your height, weight, and gender.
3. Can ideal body weight be used for children?
👉 Pediatric IBW uses separate formulas and growth charts. Our tool provides adult IBW.
4. Which is more accurate, BMI or IBW?
👉 IBW is more useful in medical settings, while BMI is more common for general health assessment.
5. Is IBW the same for men and women?
👉 No, formulas differ because men usually have more lean muscle mass.
Conclusion
Our free Ideal Body Weight Calculator makes it easy to find your healthy weight range based on multiple scientific formulas. Whether you’re checking for fitness, diet planning, or medical purposes, this tool gives you accurate results along with ABW, BMI, and LBW.
Remember, IBW is just one part of the puzzle. Combine it with other health indicators like body fat percentage, lifestyle, and physical activity for the best overall assessment.
👉 Use the calculator above now to calculate your ideal body weight and take the first step toward a healthier lifestyle.