# Body Surface Area Calculator (BSA)

URL: https://speedycalculator.com/calculators/health/body-surface-area/
Last updated: 2026-10-25

> The body surface area calculator estimates BSA in square metres from height and weight using the Mosteller formula, with the Du Bois formula for comparison. BSA is used in chemotherapy dosing, burns and cardiac index.

## Inputs

- Height (cm, m, mm, in, ft)
- Weight (kg, lb, g, oz, st)

## Results

- BSA (Mosteller)
- BSA (Du Bois)

## Formula

```
Mosteller: BSA = √(height cm × weight kg ÷ 3600)
Du Bois: BSA = 0.007184 × W^0.425 × H^0.725
```

## Explanation

Body surface area tracks metabolic size better than weight alone, which is why it is used in several clinical calculations.

### How to use the Body Surface Area Calculator

- **Height**
- **Weight**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Mosteller multiplies height and weight, divides by 3600 and takes the square root.

### Inputs explained

FieldWhat to enterHeightUnits: cm, m, mm, in, ftWeightUnits: kg, lb, g, oz, st

### What each result means

- **BSA (Mosteller)** = sqrt([Height]×[Weight]÷3600)
- **BSA (Du Bois)** = 0.007184 × [Weight]^0.425 × [Height]^0.725

### Example values

How the main result changes when **Height** changes and everything else stays at the example values above:

Height (cm)BSA (Mosteller) (m²)87.51.304131.251.5981751.845218.752.062
*Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.*

## Worked example

Inputs — Height: 175 cm; Weight: 70 kg.

Results — **BSA (Mosteller) = 1.845 m²**; BSA (Du Bois) = 1.848 m².

## Key terms

- **BSA**: Body surface area.

## FAQ

**What is a typical adult BSA?**
About 1.9 m² for men and 1.6 m² for women.

**Which formula is best?**
Mosteller is the most widely used because it is simple and accurate.

**What formula does the Body Surface Area Calculator use?**
Mosteller: BSA = √(height cm × weight kg ÷ 3600).


## Sources

- [Mosteller RD. Simplified calculation of body-surface area. N Engl J Med, 1987](https://pubmed.ncbi.nlm.nih.gov/3657876/)