BMI for 151 cm and 40 kg
A person 151 cm (4'11") tall weighing 40 kg (88 lbs) has a BMI of 17.5 — classified as Underweight. The healthy weight range for this height is 42.2–56.8 kg.
Your BMI score
Quick health screening — not a diagnosis
Your BMI suggests you may be under the recommended weight range.
What this means
BMI is a quick screening number based only on height and weight. It doesn't distinguish muscle from fat, and shouldn't replace a clinical assessment.
- 18.5–24.9 generally lowest health risk
- 25–29.9 elevated metabolic risk
- 30+ higher long-term risk
BMI range
WHO adult classification
- Severe thinness< 16
- YouUnderweight16 – 18.5
- Normal18.5 – 24.9
- Overweight25 – 29.9
- Obese I30 – 34.9
- Obese II35 – 39.9
- Obese III≥ 40
What does this BMI mean?
Underweight · BMI 17.5 · Underweight
17.5 is in the underweight band. At 151 cm, adding around 2.2 kg would bring weight into the standard healthy range.
Sustained low BMI can be linked to nutritional gaps, reduced bone density, or low energy. If the result is unintentional, a clinician check-up and basic blood work are sensible next steps.
Treat this as a starting point, not a verdict. BMI ignores muscle mass, body shape, and individual context — it's a quick number for a population, not a personal health score.
For someone 151 cm tall, weights between 42.2 kg and 56.8 kg fall in the BMI 18.5–24.9 healthy range — roughly 93–125 lbs.
How far from the healthy range?
Target BMI milestones
Weights that would land at common BMI thresholds for 151 cm.
| Milestone | Target weight | vs current |
|---|---|---|
| BMI 18.5 (lower healthy bound) | 42.2 kg(93 lbs) | Gain ~2.2 kg |
| BMI 20 (low-healthy) | 45.6 kg(101 lbs) | Gain ~5.6 kg |
| BMI 22 (mid-healthy) | 50.2 kg(111 lbs) | Gain ~10.2 kg |
Why BMI isn't the whole story
- Muscle vs fat: BMI treats a kilogram of muscle the same as a kilogram of fat. Strength athletes and very muscular builds can land in the overweight band while having low body fat.
- Body shape matters: Two people at the same BMI can carry weight very differently. Waist circumference and waist-to-height ratio capture risk that BMI misses.
- Age, sex, ethnicity: The 18.5–24.9 window is a single global average. Cutoffs adjusted for ethnicity and age can shift the interpretation, especially at the edges of the band.
- Still useful: BMI remains widely used because it's cheap, fast, and roughly predictive at population scale. Treat it as a self-check signal, not a diagnosis.
Nearby BMI combinations
Related
Common questions
Last updated: 2026