Pediatric BSA Dose Calculator

Enter a child's height and weight to calculate BSA with Mosteller or DuBois formulas, then compute a drug dose in mg from a prescribed dose per m².

Patient Measurements

Leave blank to calculate BSA only.

Body Surface Area (BSA)

Mosteller
DuBois

Mosteller: √[(H cm × W kg) / 3600]. DuBois: 0.007184 × H0.725 × W0.425.

Formula Reference

Mosteller: BSA = √[(height cm × weight kg) ÷ 3600]
DuBois: BSA = 0.007184 × H0.725 × W0.425

Results are estimates. Protocol-specific BSA caps (e.g., 2.0 m²) are applied by the prescriber, not this tool.

Summary

Enter a child's height and weight to calculate BSA with Mosteller or DuBois formulas, then compute a drug dose in mg from a prescribed dose per m².

How it works

  1. Enter the child's height (cm or inches) and weight (kg or lb).
  2. Select the BSA formula: Mosteller (most common in pediatrics) or DuBois.
  3. The calculator computes BSA in m² using the chosen formula.
  4. Enter the prescribed dose in mg per m² (mg/m²).
  5. The tool multiplies BSA by the mg/m² dose to give the total dose in mg.
  6. Review both formula results side by side to compare estimates.

Use cases

  • Calculate a chemotherapy dose for a pediatric oncology patient.
  • Determine the correct methotrexate dose for a child based on BSA.
  • Verify a prescribed BSA-based drug dose against your own calculation.
  • Compare Mosteller vs DuBois BSA estimates for the same patient.
  • Support pharmacokinetics coursework and clinical education.
  • Estimate BSA-based dosing for immunosuppressant therapy in children.
  • Double-check a dose before dispensing in a pediatric pharmacy.
  • Teach the difference between mg/kg and mg/m² dosing paradigms.

Frequently Asked Questions

Last updated: 2026-07-24 · Reviewed by Nham Vu