Measure consistently
Use independently verified height and weight when BSA informs clinical care. Never copy a casual calculator result into a dosing decision.
Body-surface-area equation audit
Compare five BSA formulas without calculating a medical dose.
Calculate Mosteller, Du Bois, Haycock, Gehan–George and Boyd body surface area, then inspect their spread and weight sensitivity.
The calculation runs locally in this browser. Educational outputs do not replace professional assessment, diagnosis, treatment or emergency care.
Method and interpretation guide
Use the body-surface-area result as a transparent estimate
Use independently verified height and weight when BSA informs clinical care. Never copy a casual calculator result into a dosing decision. The worksheet exposes its assumptions so the result can be checked instead of accepted as a black box.
Read the assumptions
BSA formulas were developed in different populations and use different exponents. The clinical protocol—not the smallest spread—determines the required method.
Escalate important decisions
A calculator cannot examine symptoms, medical history, medication effects or measurement quality. Use qualified professional guidance when the decision has health consequences.
Local calculation
Inputs are processed in this browser. No account or external calculator is required to produce the result.
False precision
Extra decimal places do not remove biological variation, input error or limits in the underlying population equation.
Scope
BSA formulas were developed in different populations and use different exponents. The clinical protocol—not the smallest spread—determines the required method.
Simple by design
Three steps to a clearer number.
Enter your details
Use realistic values in each field. You can change them anytime.
Calculate instantly
The formula runs locally, so there is no account or waiting time.
Use the result
Treat the answer as a practical estimate for your next decision.