Common BMI mistakes
- Height in the wrong unit: entering 5.6 for 5 ft 6 in — use separate feet and inches boxes.
- Weighing in shoes and clothes: can add 1–2 kg and nudge you into another category.
- Using adult ranges for teenagers: under 20, BMI must be read as a percentile for age and sex.
- Reading BMI during pregnancy: use your pre-pregnancy BMI instead.
What to do with your result
If you are in the healthy range, keep up regular activity and recheck now and then. If you are above it, even a 5% weight loss can improve blood pressure and blood sugar. If you are below 18.5, ask your doctor to look for causes such as diet, thyroid problems or other illness. In every case, a GP or nurse can put your BMI in context with your waist, family history and blood tests.
Healthy weight in pounds by height
The weight range in pounds that gives a BMI from 18.5 to 24.9 at each height, and the weight at which BMI reaches 30:
| Height | Healthy weight (BMI 18.5–24.9) | BMI 30 (obesity) from |
|---|---|---|
| 4 ft 10 in | 89 lb – 119 lb | 144 lb |
| 5 ft 0 in | 95 lb – 127 lb | 154 lb |
| 5 ft 2 in | 101 lb – 136 lb | 164 lb |
| 5 ft 4 in | 108 lb – 145 lb | 175 lb |
| 5 ft 6 in | 115 lb – 154 lb | 186 lb |
| 5 ft 8 in | 122 lb – 164 lb | 197 lb |
| 5 ft 10 in | 129 lb – 174 lb | 209 lb |
| 6 ft 0 in | 136 lb – 184 lb | 221 lb |
| 6 ft 2 in | 144 lb – 194 lb | 234 lb |
| 6 ft 4 in | 152 lb – 205 lb | 246 lb |