What formulas does the Body Surface Area Calculator use?

It computes BSA three ways: Mosteller (sqrt(height in cm × weight in kg ÷ 3600)), Du Bois & Du Bois (0.007184 × weight^0.425 × height^0.725), and Haycock (0.024265 × weight^0.5378 × height^0.3964), then shows the average of all three.

Which BSA formula is most accurate, Mosteller or Du Bois?

Mosteller is simpler and widely used in clinical practice for its ease of calculation, while Du Bois is an older, still-common reference formula. Both are estimates — the Body Surface Area Calculator shows both plus Haycock so you can compare.

What is body surface area used for?

BSA is commonly referenced for chemotherapy and other drug dosing, cardiac index calculations, and burn assessment. This calculator gives a general estimate only — actual clinical dosing must be verified by a qualified professional.

Does the Body Surface Area Calculator work in US units?

Yes. Toggle to US units to enter weight in pounds and height in feet and inches — the calculator converts to kilograms and centimetres internally before applying each formula.

Is the Body Surface Area Calculator a substitute for medical advice?

No. It is a general estimate using standard published formulas, not medical advice. Always verify dosing or clinical figures with a healthcare professional.

Body Surface Area Calculator Online

Estimate body surface area from weight and height using the Mosteller, Du Bois and Haycock formulas, right in your browser. A general estimate, not medical advice.

The Body Surface Area Calculator runs entirely in your browser. The weight and height you enter never leave your device and nothing is uploaded to ArrayKit. This tool gives a general estimate from standard formulas and is not medical advice.

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About Body Surface Area Calculator

Body Surface Area Calculator estimates BSA — the total surface area of the human body — from your weight and height using three widely referenced formulas: Mosteller, Du Bois & Du Bois, and Haycock. Switch between Metric (kilograms and centimetres) and US (pounds and feet/inches) units, and the tool shows each formula's result side by side along with the average, in square metres. It is handy for quickly cross-checking a BSA figure used in clinical references, dosing tables, or physiology coursework, or for comparing how the different formulas diverge for a given body size. Built for students, clinicians double-checking a number, and anyone curious about their own estimate. Everything computes instantly on your device — your weight and height are never uploaded. BSA is a general estimate from standard formulas and does not replace medical advice or clinical dosing decisions from a healthcare professional.

Features

Calculates BSA using the Mosteller, Du Bois & Du Bois, and Haycock formulas at once
Toggle between Metric (kg/cm) and US (lb/ft-in) units
Shows each formula's result plus the average, all in square metres
Copy a plain-text summary of every BSA figure in one click
Instant results as you type, with no page reloads
Clear error message for missing or invalid weight or height
Runs entirely in your browser — your figures never leave your device
Useful for cross-checking dosing references or physiology coursework

How to use the Body Surface Area Calculator

Choose Metric or US units
Enter your weight and height
Read the BSA from each formula and the average
Copy the summary or adjust the numbers to compare formulas

Example

Input

70 kg, 170 cm

Output

BSA: 1.82 m² (Mosteller)

sqrt(170 × 70 ÷ 3600) = 1.82 m², close to the Du Bois and Haycock results for the same inputs.

Common errors & troubleshooting

Body Surface Area Calculator shows an error even though numbers were entered. — Make sure weight and height are both greater than zero — in US mode, fill in at least the feet or inches field for height.
Result looks way too high or too low after switching units. — Switching between Metric and US keeps each unit's fields separate, so re-enter your weight and height in the newly selected unit system.
Height entered in metres instead of centimetres gives an oversized BSA. — The Metric height field expects centimetres (e.g. 170, not 1.70) — the Body Surface Area Calculator converts to metres internally.
Mosteller, Du Bois and Haycock give slightly different numbers. — This is expected — the formulas were derived from different reference populations, so a small spread (a few hundredths of a square metre) between them is normal.

Frequently asked questions

What formulas does the Body Surface Area Calculator use?: It computes BSA three ways: Mosteller (sqrt(height in cm × weight in kg ÷ 3600)), Du Bois & Du Bois (0.007184 × weight^0.425 × height^0.725), and Haycock (0.024265 × weight^0.5378 × height^0.3964), then shows the average of all three.
Which BSA formula is most accurate, Mosteller or Du Bois?: Mosteller is simpler and widely used in clinical practice for its ease of calculation, while Du Bois is an older, still-common reference formula. Both are estimates — the Body Surface Area Calculator shows both plus Haycock so you can compare.
What is body surface area used for?: BSA is commonly referenced for chemotherapy and other drug dosing, cardiac index calculations, and burn assessment. This calculator gives a general estimate only — actual clinical dosing must be verified by a qualified professional.
Does the Body Surface Area Calculator work in US units?: Yes. Toggle to US units to enter weight in pounds and height in feet and inches — the calculator converts to kilograms and centimetres internally before applying each formula.
Does the Body Surface Area Calculator upload my weight and height?: No. The Body Surface Area Calculator runs entirely in your browser. The weight and height you enter never leave your device and are not uploaded to ArrayKit.
Is the Body Surface Area Calculator a substitute for medical advice?: No. It is a general estimate using standard published formulas, not medical advice. Always verify dosing or clinical figures with a healthcare professional.

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