Written and maintained by Christin Bowles, founder of TidyCalcs.
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Your healthy weight range
For your height, a healthy weight is -
What is BMI?
Body Mass Index is a measure of body fat based on height and weight. It applies to most adults aged 18-65.
BMI limitations
BMI doesn't measure body fat directly. Athletes may have high BMI due to muscle mass. Always consult a doctor.
Healthy range
A BMI between 18.5 and 24.9 is considered healthy for most adults according to the World Health Organization.
Beyond BMI
Waist circumference, diet quality, and physical activity are also important indicators of overall health.
Go deeper
Read BMI vs. Body Fat Percentage to see which number matters more for your goals, or check your daily calorie needs.
Plan your macros
Once you have a calorie target, use the Macro Calculator to split it into protein, carb, and fat grams.
How BMI is actually calculated
BMI uses a straightforward formula developed by Belgian mathematician Adolphe Quetelet in the 1830s — long before it was adopted as a health screening tool. The formula is:
In imperial units: BMI = (weight in lbs x 703) / height in inches²
For example, a person who is 5'9" (175cm) and weighs 160 lbs (72.5kg) has a BMI of 23.6 — squarely in the normal range. The same person at 185 lbs would have a BMI of 27.3, crossing into overweight.
What the BMI categories actually mean
The WHO classifications most people know are based on studies of predominantly European adult populations. Here is what each category means in practice — and where the research gets more nuanced:
| Category | BMI range | Health risk |
|---|---|---|
| Underweight | Below 18.5 | Increased risk of nutritional deficiency, osteoporosis, immune issues |
| Normal weight | 18.5 – 24.9 | Lowest risk for most chronic diseases in most populations |
| Overweight | 25.0 – 29.9 | Modestly increased risk — research shows fit people in this range often have good outcomes |
| Obese class I | 30.0 – 34.9 | Increased risk of type 2 diabetes, heart disease, hypertension |
| Obese class II | 35.0 – 39.9 | High risk — significant cardiovascular and metabolic impact |
| Obese class III | 40.0 and above | Very high risk — also called severe or morbid obesity |
For people of Asian descent, health risks associated with excess body fat appear at lower BMI values. The WHO suggests considering action points at BMI 23 (overweight) and 27.5 (obese) for Asian populations, compared to 25 and 30 for other groups.
Where BMI falls short — and what to use instead
BMI has one major blind spot: it cannot distinguish between fat mass and muscle mass. A 200 lb person who is 5'10" has a BMI of 28.7 whether they are a competitive athlete or sedentary. The number is identical; the health picture is completely different.
Athletes and muscular people
May register as overweight or obese despite low body fat. Muscle is denser than fat, pushing BMI higher without any health risk.
Older adults
Tend to lose muscle and gain fat with age. BMI may look normal while body fat percentage is actually elevated — a condition called "normal weight obesity."
Shorter people
BMI tends to underestimate fatness in shorter individuals. The squaring of height in the formula doesn't scale perfectly across all body sizes.
Better alternatives
Waist-to-height ratio, waist circumference, and body fat percentage give a more complete picture of health risk than BMI alone.
Healthy weight ranges by height
Based on the WHO normal BMI range of 18.5 to 24.9, here are the healthy weight ranges for adults at every height from 4'10" to 6'4". The midpoint is the weight at a BMI of about 21.7, right in the middle of the healthy range.
| Height | Healthy weight range | Midpoint |
|---|---|---|
| 4'10" (147cm) | 89 – 119 lbs (40 – 54 kg) | 104 lbs |
| 4'11" (150cm) | 92 – 123 lbs (42 – 56 kg) | 107 lbs |
| 5'0" (152cm) | 95 – 128 lbs (43 – 58 kg) | 111 lbs |
| 5'1" (155cm) | 98 – 132 lbs (44 – 60 kg) | 115 lbs |
| 5'2" (157cm) | 101 – 136 lbs (46 – 62 kg) | 119 lbs |
| 5'3" (160cm) | 104 – 141 lbs (47 – 64 kg) | 123 lbs |
| 5'4" (163cm) | 108 – 145 lbs (49 – 66 kg) | 126 lbs |
| 5'5" (165cm) | 111 – 150 lbs (50 – 68 kg) | 130 lbs |
| 5'6" (168cm) | 115 – 154 lbs (52 – 70 kg) | 134 lbs |
| 5'7" (170cm) | 118 – 159 lbs (54 – 72 kg) | 139 lbs |
| 5'8" (173cm) | 122 – 164 lbs (55 – 74 kg) | 143 lbs |
| 5'9" (175cm) | 125 – 169 lbs (57 – 76 kg) | 147 lbs |
| 5'10" (178cm) | 129 – 174 lbs (58 – 79 kg) | 151 lbs |
| 5'11" (180cm) | 133 – 179 lbs (60 – 81 kg) | 156 lbs |
| 6'0" (183cm) | 136 – 184 lbs (62 – 83 kg) | 160 lbs |
| 6'1" (185cm) | 140 – 189 lbs (64 – 86 kg) | 164 lbs |
| 6'2" (188cm) | 144 – 194 lbs (65 – 88 kg) | 169 lbs |
| 6'3" (191cm) | 148 – 199 lbs (67 – 90 kg) | 174 lbs |
| 6'4" (193cm) | 152 – 205 lbs (69 – 93 kg) | 178 lbs |
Common questions
How do I calculate my BMI?
Enter your weight and height above and click "Calculate my BMI." The calculator instantly shows your BMI score, category, and healthy weight range for your height.
What is a healthy BMI?
For most adults, a BMI between 18.5 and 24.9 is considered healthy. Below 18.5 is underweight, 25-29.9 is overweight, and 30 or above is obese.
Is BMI accurate for everyone?
BMI is a useful screening tool but has limitations. It may overestimate body fat in athletes and underestimate it in older adults. It also does not account for muscle mass, bone density, or fat distribution.
What is BMI Prime?
BMI Prime is your BMI divided by 25 (the upper limit of normal BMI). A BMI Prime of 1.0 means you are exactly at the upper limit of the healthy range. Below 1.0 is healthy or underweight, above 1.0 is overweight or obese.
How much should I weigh for my height?
The healthy weight range depends on your height. Our calculator shows your personalized healthy weight range based on the normal BMI range of 18.5 to 24.9.
Is BMI calculated differently for children and teenagers?
Yes. For people under 20, BMI is plotted on age- and sex-specific growth charts as a percentile rather than compared to the fixed adult categories, since body composition changes significantly during growth. This calculator uses the adult formula and categories, so it isn't appropriate for children or teens; a pediatrician or the CDC's BMI-for-age charts should be used instead.
Can you have a normal BMI but still have too much body fat?
Yes, this is sometimes called "normal weight obesity" or being "skinny fat." It happens most often in older adults and people who have lost muscle mass over time, when weight and BMI stay in the normal range but body fat percentage is elevated relative to muscle. Because BMI can't distinguish fat from muscle, someone in this situation can carry the same metabolic risks as someone classified as overweight, which is why waist circumference or body fat percentage are useful alongside BMI.
Does BMI mean the same thing for men and women?
The BMI formula and category cutoffs are the same for men and women, but the two sexes typically carry body fat differently at the same BMI. Women generally have a higher percentage of body fat than men at an equivalent BMI, since men tend to carry more muscle mass. This is one reason BMI is best treated as a screening tool rather than a precise measure of body fat for any individual, regardless of sex.
Sources and further reading
For independent, authoritative information on this topic, these are good places to start:
- Centers for Disease Control and Prevention: Adult BMI categories — the official category ranges for adults.
- Centers for Disease Control and Prevention: About BMI — what BMI measures and how it is used as a screening tool.
- National Heart, Lung, and Blood Institute: Calculate your BMI — the NIH's own calculator, useful for cross-checking results.
Results are estimates for general information and are not medical advice. A doctor or registered dietitian can give guidance specific to you.