BMI for 150 cm and 40 kg
A person 150 cm (4'11") tall weighing 40 kg (88 lbs) has a BMI of 17.8 — classified as Underweight. The healthy weight range for this height is 41.6–56.0 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 17.8 · Underweight
A BMI of 17.8 is below the lower healthy bound of 18.5. For 150 cm, the healthy weight range starts at about 41.6 kg, so this result sits roughly 1.6 kg under that.
Being underweight isn't automatically a problem, but it can come with lower iron, B12, or calorie reserves. Worth investigating if weight has dropped without trying.
BMI is a screening tool, not a diagnosis. It doesn't know the difference between fat and muscle, doesn't measure where weight sits on the body, and doesn't account for age, sex, or ethnicity-specific cutoffs.
For someone 150 cm tall, weights between 41.6 kg and 56.0 kg fall in the BMI 18.5–24.9 healthy range — roughly 92–124 lbs.
How far from the healthy range?
Target BMI milestones
Weights that would land at common BMI thresholds for 150 cm.
| Milestone | Target weight | vs current |
|---|---|---|
| BMI 18.5 (lower healthy bound) | 41.6 kg(92 lbs) | Gain ~1.6 kg |
| BMI 20 (low-healthy) | 45.0 kg(99 lbs) | Gain ~5.0 kg |
| BMI 22 (mid-healthy) | 49.5 kg(109 lbs) | Gain ~9.5 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