You know you want to lose weight, but what's actually "ideal" for you? Is it 120 pounds? 150? The answer isn't a single magical number-it's a range based on your specific height, age, and body frame. Your ideal weight calculator finds that personalized range, giving you a realistic target grounded in science and your unique body.
What This Calculator Does
Your ideal weight calculator uses the Devine and Miller formulas-established medical equations that consider height, age, and sex to determine healthy weight ranges. Unlike BMI (which flags a range of weights), your ideal weight calculator computes a specific target range tailored to you. It accounts for the fact that a muscular 5'10" person will weigh more than a lean 5'10" person at the same healthy fitness level. You get not a single number, but a band you can aim for.
How to Use This Calculator
Enter your height (in feet and inches, or centimeters), your sex, and your age. For the most personalized results, indicate your frame size: small, medium, or large. You can estimate frame size by feeling your wrist-if you can wrap your thumb and middle finger around it with a gap, you're medium; barely touching or overlapping means small; if they don't touch, you're large. The calculator then displays your ideal weight range, based on medical formulas, adjusted for your frame and age.
The Formula Behind the Math
Your ideal weight calculator uses the Devine formula as a baseline, then adjusts for frame size and age:
Devine Formula (baseline):
Frame adjustments:
Age adjustment: Older adults may have slightly higher healthy weights due to natural muscle loss with age.
Let's work through an example. A 35-year-old woman, 5'6" (66 inches), medium frame:
This gives her a realistic range. At 162 pounds, she'd be lean with good muscle definition. At 200 pounds, she'd be fit and healthy with more muscle mass. Anywhere in between is a valid healthy weight depending on her body composition.
Our calculator does all of this instantly-but now you understand exactly what it's computing.
Ideal Weight vs. Goal Weight: Know the Difference
Your ideal weight range is what research suggests is healthy for your body. Your goal weight is where you personally want to be. These might overlap, or your goal might be more ambitious. A woman with an ideal range of 125-155 pounds might personally set a goal of 130 pounds because that's where she feels her best and strongest. Her goal is within the ideal range, and it's sustainable. You don't have to aim for the top or bottom of the ideal range-pick where you feel good.
How Frame Size Affects Your Target
This is where many people go wrong. A large-frame 5'10" man might have a healthy weight of 180-200 pounds, while a small-frame 5'10" man might be healthy at 160-175. The same height, completely different healthy weights. This is why "you should weigh 170 pounds" generic advice fails-it ignores body structure. Your ideal weight calculator accounts for this. A woman shouldn't feel bad if her healthy range tops out at 160 when a friend at the same height is healthy at 140—frame size matters tremendously.
Using Ideal Weight for Realistic Goal Setting
If you're currently 220 pounds and your ideal weight range is 145-165 pounds, that's a 55-75 pound loss. That's a multi-year project at a healthy pace, not a summer goal. But now you have something concrete: a range to work toward. You can set interim goals-hit 200 by next year, 175 by the year after. Ideal weight gives you direction and realistic timelines instead of vague aspirations.
Muscle Changes Everything
Ideal weight assumes average body composition. If you start strength training, you'll build muscle. Muscle weighs more than fat at the same volume. Two women both 5'6", both in the ideal weight range of 120-145 pounds, might look dramatically different: one sedentary with 30% body fat, one athletic with 20% body fat. Same weight, different look. This is why ideal weight is a range, not a target. Within that range, strength training shifts how you look without moving the scale.
Tips and Things to Watch Out For
Use your ideal weight range as guidance, not law. Medical formulas are based on population averages. You're an individual. If you feel strong, energized, and healthy at the top of your range, that's your ideal weight. If you feel best at the bottom, great-that's your number. The range gives you freedom; it doesn't demand you hit a specific point.
Account for bone density and muscle when interpreting your range. Athletes naturally weigh more. Someone with dense bones weighs more. These variations are normal. If you're in your ideal range and feel great, you're in the right place, even if you look lighter or heavier than expected.
Remember that age affects your ideal weight slightly. As you age, your metabolism slows and muscle naturally decreases unless you actively work against it. Your ideal weight might gradually increase slightly over decades, not because it's "healthy to gain weight," but because your body composition naturally shifts. Staying the same weight might actually mean relative fat gain if you lose muscle.
Don't aim for the low end of the range unless you're an athlete or very lean naturally. Many people set a goal at the low end of their ideal weight range and struggle to maintain it because it's unsustainably lean for them. The middle of your range is often the sweet spot: healthy, sustainable, and maintainable long-term without obsessive dieting.
This calculator provides general health information only. Always consult a qualified healthcare provider before making any medical or health decisions.
Frequently Asked Questions
What's the difference between ideal weight and healthy weight?
Ideal weight is calculated based on height, frame, and sex-it's the medical recommendation. Healthy weight is where you feel good, function well, and have good health markers. These usually overlap. Your ideal weight range gives you a target; within that range, your personal healthy weight is where you feel your best.
How accurate is the ideal weight calculator?
The Devine and Miller formulas are based on population averages and are reasonably accurate for most people. Individual variation exists based on factors like muscle mass, bone density, and genetics. Use the calculated range as your target zone, but if you feel healthy and energetic at a weight outside the range, your body may be telling you something the formula misses.
Can I be healthy above my ideal weight range?
Possibly, depending on your body composition. If you're very muscular, you might weigh more than the range suggests and be perfectly healthy. If you're above the range and sedentary, you might benefit from moving toward it. The range is a guide based on averages, not an absolute rule. Your doctor's assessment of your health markers matters more than the number.
Should I use my ideal weight if I have a medical condition?
Medical conditions sometimes affect appropriate weight targets. Thyroid disorders, PCOS, and others can shift your metabolism. Talk with your doctor about what weight range is appropriate for your specific situation. Your doctor might recommend adjusting your goal based on your health profile.
How long should it take to reach my ideal weight?
A safe rate is 1-2 pounds per week, which translates to roughly 4-8 pounds per month. If you need to lose 50 pounds, that's 6-12 months of consistent effort. If you need to lose 20 pounds, that's 2-5 months. Setting interim goals every 10 pounds keeps you motivated and lets you celebrate progress along the way.
What if my current weight is below my ideal range?
If you're healthy, energetic, and strong below your ideal range, you're fine where you are. The ideal range is a guide for population averages-some people are healthy below it. If you're below the range and struggling with fatigue, weakness, or other issues, discussing this with your doctor makes sense. Gaining weight to reach the range might improve your health, or might not be necessary.
Related Calculators
Your ideal weight range provides direction, but you need calorie and nutrition targets to get there. Use the Calorie Calculator to determine how much to eat daily to reach your goal weight. The BMI Calculator provides a complementary height-to-weight assessment. The Body Fat Percentage Calculator shows you what your body composition actually is, which matters more than the number on the scale. Together, these tools give you a complete roadmap to your goals.