Your result
What your result means
At 5 ft 9 in and 170 lb, your BMI is 25.1, which the CDC classifies as “Overweight” for adults 20 and older. For your height, a BMI between 18.5 and 24.9 corresponds to 125 lb – 169 lb; you are about 1 lb above that range. BMI is a screening number only — it does not measure body fat directly.
The math
Formula and sources
BMI = weight (kg) ÷ height (m)² US units: BMI = 703 × weight (lb) ÷ height (in)²
- Underweight
- below 18.5
- Healthy weight
- 18.5 to < 25
- Overweight
- 25 to < 30
- Obesity
- 30 or higher
How to calculate BMI with pounds and inches: BMI = 703 × weight (lb) ÷ height (in)². Example: 5 ft 4 in is 64 in; at 140 lb, 703 × 140 ÷ 64² ≈ 24.0. We convert pounds and inches with the exact factors (1 lb = 0.45359237 kg, 1 in = 2.54 cm), which is what the 703 shortcut approximates. Children and teens use age- and sex-specific percentiles instead of these adult cutoffs.
Sources we checked this against
- 1Adult BMI Categories / BMI Frequently Asked QuestionsCenters for Disease Control and Prevention · cdc.gov
- 2Calculate Your Body Mass IndexNational Heart, Lung, and Blood Institute (NIH) · nhlbi.nih.gov
Formula last checked 2026-11-05. Found an error? Tell us and we will fix it.
Data: See the healthy weight range for every height (published formulas and CDC ranges, free CSV).
Data: See the BMI weights for a 5'4" woman (and every height from 4'10" to 6'6") (published formulas and CDC ranges, free CSV).
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BMI by height
BMI chart by height for women and men
The first whole pound at which each adult BMI category begins, by height. BMI uses the same cut-offs for women and men, so a 5'4" woman has a healthy BMI (18.5 to 24.9) at 108–145 lb, reaches overweight (BMI 25) at 146 lb and obesity (BMI 30) at 175 lb. Select a height for the full row, with ideal weight by formula, on the ideal weight chart.
| Height | Healthy weight (BMI 18.5–24.9) | Overweight from (BMI 25) | Obesity from (BMI 30) |
|---|---|---|---|
| 5'0" (152 cm) | 95–128 lb | 129 lb | 154 lb |
| 5'1" (155 cm) | 98–132 lb | 133 lb | 159 lb |
| 5'2" (157 cm) | 102–136 lb | 137 lb | 165 lb |
| 5'3" (160 cm) | 105–141 lb | 142 lb | 170 lb |
| 5'4" (163 cm) | 108–145 lb | 146 lb | 175 lb |
| 5'5" (165 cm) | 112–150 lb | 151 lb | 181 lb |
| 5'6" (168 cm) | 115–154 lb | 155 lb | 186 lb |
| 5'7" (170 cm) | 119–159 lb | 160 lb | 192 lb |
| 5'8" (173 cm) | 122–164 lb | 165 lb | 198 lb |
| 5'9" (175 cm) | 126–169 lb | 170 lb | 204 lb |
| 5'10" (178 cm) | 129–174 lb | 175 lb | 210 lb |
| 5'11" (180 cm) | 133–179 lb | 180 lb | 216 lb |
| 6'0" (183 cm) | 137–184 lb | 185 lb | 222 lb |
| 6'1" (185 cm) | 141–189 lb | 190 lb | 228 lb |
| 6'2" (188 cm) | 145–194 lb | 195 lb | 234 lb |
Each cut-off is the first whole pound at that BMI. Adults only; children and teens use CDC BMI-for-age percentiles.
Step by step
Two worked examples
CDC’s example adult
Your BMI
30.4
- Units
- US (ft, in, lb)
- Height (feet)
- 5 ft
- Height (inches)
- 8 in
- Weight
- 200 lb
The CDC uses a 5 ft 8 in adult weighing 200 lb: 703 × 200 ÷ 68² = 30.4, in the “Obesity” category.
Same height, 150 lb
Your BMI
22.8
- Units
- US (ft, in, lb)
- Height (feet)
- 5 ft
- Height (inches)
- 8 in
- Weight
- 150 lb
At 150 lb the BMI falls to 22.8 — “Healthy weight”. The healthy range for 5 ft 8 in is 122 lb – 164 lb.
| Result | Example 1 | Example 2 |
|---|---|---|
| Your BMI | 30.4 | 22.8 |
| Category | Obesity | Healthy weight |
| Compared with that range | about 36 lb above | within |
Questions
Frequently asked questions
Is BMI accurate for athletes?
Not very. Muscle is dense, so muscular people can have a high BMI with little body fat. A waist measurement or a body fat estimate gives more context.
Does BMI differ for men and women?
For adults the same categories apply regardless of sex or age. Women tend to carry more body fat than men at the same BMI, which is one reason BMI is only a screening tool.
Can I use this for my child?
No. For ages 2 to 19, BMI must be compared with growth charts for the child’s age and sex. Use the CDC’s Child and Teen BMI Calculator.
What should I do if my BMI is out of range?
Treat it as a prompt for a conversation with a healthcare professional, who can look at blood pressure, lab results, waist size and other factors.
How much BMI is considered obese?
For adults 20 and older, the CDC classifies BMI of 30.0 or higher as obesity. The full adult categories are: underweight below 18.5, healthy weight 18.5 to less than 25, overweight 25 to less than 30, and obesity 30 or higher (with class 1 = 30–34.9, class 2 = 35–39.9, class 3 = 40+). BMI is a screening number only; muscle, age and waist size matter too. See the CDC’s Adult BMI page for the official ranges.
What is a good BMI for women over 50?
Adult BMI categories do not change with age or sex: 18.5–24.9 is the CDC healthy-weight range for women over 50 as well. Body composition often shifts after menopause, so many clinicians also look at waist circumference, blood pressure and labs. A “good” number is one your clinician agrees fits your health picture — BMI alone is not a diagnosis.