Ideal Weight Calculator
This free ideal weight calculator shows a healthy weight range for your height, plus the classic formula estimates, based on your height and sex. There’s no single “perfect” number, so we give you a sensible range to aim for rather than one figure to obsess over.
What your result means
The big number is a healthy weight range for your height, worked out from a healthy body mass index (BMI 18.5 to 24.9). Any weight inside that range is generally considered healthy, which is why it’s far more useful than a single “ideal” figure.
The three cards show the classic ideal body weight formulas, Devine, Robinson, and Hamwi, that doctors have used for decades. Notice how close they are to each other, and how they sit near the middle of your healthy range. Treat them as a rough single-number reference, not a strict goal. Where you feel and function best inside the range matters more than hitting one exact number.
Why “ideal weight” is really a range
It’s tempting to want one magic number, but bodies don’t work that way. Two people of the same height can both be perfectly healthy at noticeably different weights, depending on their build, muscle, and bone structure. That’s exactly why health organisations describe a healthy weight range rather than a single target.
The formulas in this tool were originally created decades ago to help doctors set medication doses, not to define the one weight you should be. They’re useful as a ballpark, but a range built from a healthy BMI is a friendlier, more realistic way to think about it, and it takes the pressure off chasing a number that was never meant to be exact.
How ideal weight is calculated
We work out your result two ways so you get the full picture. If you enter imperial units, we convert your height to centimetres first.
1. Healthy weight range (the main result)
We take the healthy BMI range of 18.5 to 24.9 and reverse it for your height: weight = BMI × height in metres squared. That gives the lowest and highest weights considered healthy for someone your height.
2. Classic formulas (the cards)
These estimate a single ideal body weight from your height and sex, adding a set amount per inch above 5 feet:
| Formula | Men | Women |
|---|---|---|
| Devine (1974) | 50 kg + 2.3/in | 45.5 kg + 2.3/in |
| Robinson (1983) | 52 kg + 1.9/in | 49 kg + 1.7/in |
| Hamwi (1964) | 48 kg + 2.7/in | 45.5 kg + 2.2/in |
They all add a fixed base plus a little for every inch over five feet, which is why they line up so closely.
What ideal weight doesn’t tell you
Here’s the honest limitation: neither a formula nor the scale knows what your weight is made of. A lean, muscular person can weigh more than their “ideal” and be very healthy, while someone at a “normal” weight can carry too little muscle. Weight is just one clue.
For a fuller picture, look at a few things together: how your clothes fit, your energy and fitness, your waist measurement, and health markers from your doctor. Tools like our BMI calculator add context, and body composition matters more than any single figure. If your goal is changing your weight, focus on sustainable habits rather than a target on the scale.
A healthier way to think about your weight
If the number on the scale stresses you out, you’re not alone, and there’s a kinder, more effective approach. Instead of fixating on one “ideal” figure:
- Aim for the range, not a point. Anywhere in your healthy range is a win.
- Judge by how you feel and function, your energy, strength, sleep, and how your clothes fit.
- Watch trends, not daily numbers. Weight bounces day to day from water and food; the direction over weeks is what counts.
- Build habits, not targets. Regular movement and balanced eating naturally guide your body toward a healthy weight over time.
New to all this? Our beginner home-workout guide and Start Here page are gentle places to begin.
Common mistakes to avoid
- Treating a formula number as a strict goal. The single figures are rough estimates from decades ago, not a precise target you must hit.
- Assuming lower is always healthier. Aiming for the very bottom of your range isn’t better; being under a healthy weight carries its own risks.
- Ignoring muscle and build. If you’re strong and active, sitting above the “ideal” figure is often perfectly healthy.
- Weighing yourself obsessively. Daily numbers swing with water and food. Check in weekly at most and watch the trend.
- Comparing yourself to others. Two people of the same height can both be healthy at different weights. Your range is yours.
How to set a realistic goal weight
If you do want a specific target to work toward, use your healthy range wisely rather than picking a random number. A sensible approach:
- Pick a point inside your range, not below it, closer to the middle is a comfortable, sustainable place to aim.
- Factor in your build. If you’re muscular or larger-framed, lean toward the upper half; it will feel more natural to maintain.
- Go slow. Aim to change weight at around half a kilogram to one kilogram (one to two pounds) a week at most.
- Focus on the habits. Use your calorie target and regular movement to get there, and let the weight follow.
Most importantly, remember that feeling strong, energetic, and healthy matters far more than any exact figure on the scale.
Frequently asked questions
What is my ideal weight?
Rather than one number, your ideal weight is best thought of as a healthy range for your height, the range shown above, based on a BMI of 18.5 to 24.9. Anywhere in that range is generally healthy, so aim for it rather than a single figure.
What is the ideal weight for my height?
Enter your height above and you’ll get the healthy weight range for it, in kilograms or pounds, plus classic formula estimates. As a rough example, a healthy range for someone 170 cm (5 ft 7 in) tall is around 53 to 72 kg.
How do I calculate my ideal weight?
The simplest method is to work out the weight range for a healthy BMI at your height. Traditional formulas (Devine, Robinson, Hamwi) add a set amount of weight for every inch above five feet, adjusted for sex. This calculator does both for you.
What’s the ideal weight for a woman?
It depends entirely on height, not sex alone, so enter your height and select female above. The formulas use a slightly lower base for women, but the healthy range is the most useful guide. There’s no single ideal weight that applies to all women.
What’s the ideal weight for a man?
Again, height is what matters most. Select male and enter your height for your range and formula estimates. Men’s formulas start from a slightly higher base, reflecting average differences in build.
Is BMI an accurate way to judge weight?
BMI is a useful, quick screening tool for most people, but it doesn’t measure body fat directly or account for muscle. Very muscular people can be misclassified. Use it as one clue alongside how you look, feel, and function.
Does body frame or build affect ideal weight?
Yes. People with larger frames or more muscle naturally sit at the higher end of a healthy range, and that’s completely fine. It’s one more reason a range beats a single number.
What is the ideal weight for children?
This calculator is for adults only. Children and teenagers grow at different rates, so healthy weight is assessed using age-and-sex growth charts, not adult formulas. For a child, speak with your pediatrician.
Should I try to reach my exact ideal weight?
No need. Chasing one precise number often does more harm than good. Aim to be within your healthy range and, more importantly, to feel strong and energetic. Habits and health markers matter more than an exact figure.
I’m muscular, why does the calculator say I’m over my ideal weight?
Because these methods use only height and sex, they can’t tell muscle from fat. If you train regularly and carry good muscle, a higher weight can be perfectly healthy. A body-composition check tells you far more than the scale.
References
The healthy range uses the standard BMI cut-offs from the World Health Organization (healthy BMI 18.5–24.9). The single-number estimates use the long-established Devine (1974), Robinson (1983), and Hamwi (1964) ideal body weight formulas widely used in clinical practice. For general guidance, see the CDC on healthy weight.
What should I do next?
Remember, this is a healthy range, not a target you must hit. Here is where to go next.
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