Ideal Weight Calculator
Find your ideal body weight by height and sex using four medical formulas and the healthy BMI range.
If entered, the difference from your ideal weight is shown.
How to Calculate Ideal Weight by Height
If you have ever asked "what is my ideal weight?", this ideal body weight calculator gives you the answer for your height and sex. It determines the healthy weight range for your height and sex — in other words, your ideal weight for height. Several formulas have been developed in medical history; this tool calculates the four most common — Hamwi, Devine, Robinson and Miller — at once and presents them in a comparison table. Seeing a range rather than a single number lets you set more realistic weight goals.
The most scientific reference point for height-based weight is the WHO's BMI (Body Mass Index) range: a normal weight corresponds to a BMI of 18.5 – 24.9. For someone 175 cm tall this range is roughly 56.7 – 76.3 kg. If the formula results overlap with this range, you can consider yourself in the healthy weight zone.
Four Formula Comparison
Each formula has a different origin and intended use:
- Hamwi (1964): Developed for clinical diabetes management; a historical reference formula. For men, starting from 152.4 cm, 2.7 kg is added for every extra 2.54 cm.
- Devine (1974): Developed to calculate medication doses; still used in clinical drug protocols today. This Devine formula calculator adds 2.3 kg per extra 2.54 cm above 152.4 cm.
- Robinson (1983): The formula preferred in current clinical studies; adds 1.9 kg per extra 2.54 cm for men, 1.7 kg for women.
- Miller (1983): Usually gives the lowest estimate for men and a mid-level one for women; can produce a more suitable result for larger builds.
No formula is perfect for everyone. That is why the tool also shows the average of the four formulas; this average can be used as the most balanced starting point.
Ideal Weight by Age
A healthy target is far more meaningful when height, weight and age are considered together. Standard formulas use only height and sex, but age directly affects how the result should be interpreted. With age, muscle mass tends to decrease while body fat increases:
- Ages 18–40: Standard formulas (Hamwi, Devine, Robinson) can be applied directly.
- Ages 40–65: Possible loss of muscle mass should be considered; evaluate the results together with the BMI range.
- Over 65: Research suggests a BMI of 22–27 is more protective in this group; formula results may come out slightly low.
- Children under 18: Standard formulas do not apply; age- and sex-specific percentile charts are required.
Ideal Weight Chart by Height
The ideal weight chart below shows the ideal weight range corresponding to a BMI of 18.5–24.9 for common heights — a quick reference for your ideal weight for height:
| Height (cm) | Lower (kg) | Upper (kg) | Midpoint (kg) |
|---|---|---|---|
| 155 cm | 44.4 | 59.8 | 52.1 |
| 160 cm | 47.4 | 63.7 | 55.6 |
| 165 cm | 50.4 | 67.8 | 59.1 |
| 170 cm | 53.5 | 72.0 | 62.8 |
| 175 cm | 56.7 | 76.3 | 66.5 |
| 180 cm | 59.9 | 80.7 | 70.3 |
| 185 cm | 63.3 | 85.2 | 74.3 |
| 190 cm | 66.8 | 89.9 | 78.4 |
Body Frame and Ideal Weight
Bone structure (body frame) affects how much weight is healthy for you. People with a small frame fit the lower end of the range, while those with a large frame can be healthy at a slightly higher weight. As a quick check, wrap your thumb and index finger around your opposite wrist: if they overlap you likely have a small frame, if they just touch a medium frame, and if they do not meet a large frame. The tool shows a frame-based acceptable range (about ±10%) using the Robinson formula.
How to Use the Ideal Weight Calculator
Used as a healthy weight calculator, the practical answer is: first look at the BMI-based range (the broadest, most scientific reference), then compare it with the Hamwi or Robinson formula. If the two values agree, you have a reasonable target range. If there is a big difference, your bone structure and muscle mass may deviate from the standard; in that case a body fat measurement gives clearer information. The key point when working out your target weight is that these tools are a guide — healthy weight management requires calorie balance, regular exercise and enough sleep as a whole.
Steps to Reach a Healthy Weight Range
Calculators show your target range, but reaching it requires a regular, systematic approach. Here are the core steps:
- Find your starting point: Calculate your current weight, height and BMI to see how far you are from the ideal range.
- Set a realistic goal: A change of 1–2 kg per month (loss or gain) is a sustainable, healthy pace. Sudden, extreme diets do not work in the long run.
- Track your calorie balance: Estimate your daily needs (basal metabolism + activity) and keep intake and expenditure in balance.
- Measure regularly: Weigh yourself every two weeks under the same conditions (morning, before eating). Daily fluctuations can be misleading; a weekly average is more reliable.
- Get professional support: If your target weight is more than 10 kg from the ideal range, working with a dietitian or doctor improves the safety and effectiveness of the process.
Ideal Weight vs BMI — Frequently Asked
One of the most common questions is "why do formulas give different results for the same height?" The answer relates to each formula's purpose. The Devine formula was optimized for medication dosing, while the Hamwi formula began as a clinical tool for diabetes patients. For everyday use, Robinson or the average of several formulas gives a more balanced result. Another common topic is the difference between height-weight calculation and BMI calculation: BMI divides your weight by the square of your height and places you in a category, while ideal weight formulas suggest a single reference point or range for your height. The two methods complement each other; use these values as a starting point and review the results with a health professional.
Frequently Asked Questions About the Ideal Weight Calculator
For the normal BMI range of 18.5–24.9: 160 cm → 47.4–63.7 kg; 170 cm → 53.5–72.0 kg; 175 cm → 56.7–76.3 kg; 180 cm → 59.9–80.7 kg. By the Hamwi formula, the ideal for a 175 cm man is about 72.0 kg and for a woman about 65.1 kg.
Standard formulas (Hamwi, Devine, Robinson) apply for ages 18–65. Over 65, a BMI of 22–27 is considered more suitable. For children under 18, age- and sex-specific percentile charts must be used; standard ideal weight formulas do not apply to children.
No single formula is perfect for everyone. The most balanced approach is to average the four formulas, which this tool does automatically to give one recommended ideal weight. In current clinical practice, the Robinson formula is the most preferred for standard builds.
Height (cm) and sex are enough. If you also enter your current weight, you will see the difference from your ideal weight. Age is not used directly in the formulas, but you should consider your age group when interpreting the results.
BMI divides your weight by the square of your height and places you in a category (underweight, normal, overweight, obese). Ideal weight formulas suggest a single reference point or range for your height. The two methods complement each other; this tool shows both at once.
Body frame (small, medium, large bone structure) shifts the acceptable range by roughly ±10%. People with a larger frame can be healthy at a slightly higher weight, while those with a smaller frame fit a lower range. The tool shows a frame-based acceptable range using the Robinson formula.
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