# Dose by Body Surface Area Calculator (BSA = √(H·W/3600)) Calculate an individualized drug dose from body surface area using the Mosteller formula: BSA (m²) = √(Height(cm) · Weight(kg) / 3600), then Dose = Drug_dose_per_m² × BSA. BSA is the recommended normalization for many cytotoxic and pediatric regimens because drug clearance scales more linearly with BSA than with body weight across patients of different sizes. Also reports the standard adult dose at the reference adult BSA of 1.73 m² for comparison. Valid only for linear drug clearance — BSA dosing does not apply to saturable (Michaelis-Menten) pathways. Not medical advice. > Canonical page: https://elysiatools.com/en/tools/dose-by-body-surface-area - **Category:** Health - **Keywords:** body surface area, BSA, Mosteller, dose per m2, mg/m2, chemotherapy, pediatric dosing, height, weight, pharmacokinetics, pk, drug, medicine ## Overview Calculate body surface area (BSA) with the Mosteller formula and estimate a drug dose from a prescribed dose per square meter. Enter height, weight, and dose per m² to receive BSA, individualized dose, and the standard adult comparison at 1.73 m². This calculator is for linear drug clearance models and is not medical advice. ## Inputs - **Height (cm)** (number): Body height in centimeters. Must be positive. - **Weight (kg)** (number): Body weight in kilograms. Must be positive. - **Drug dose per m² (mg/m²)** (number): Drug dose per square meter of BSA. Must be positive. - **Decimal Places** (number) ## When to use - Estimate a dose from height, weight, and a prescribed value in mg/m². - Calculate BSA for reviewing pediatric or cytotoxic dosing regimens that use body surface area. - Compare an individualized dose with the standard adult dose based on a reference BSA of 1.73 m². ## How it works - Enter height in centimeters, weight in kilograms, and the drug dose per square meter in mg/m². - The calculator applies the Mosteller formula: BSA = √(height × weight / 3600). - It calculates the dose as dose per m² × BSA. - The result also shows the standard adult dose calculated with a reference BSA of 1.73 m²; decimal places can be set from 0 to 8. ## Use cases - Reviewing dose-per-m² calculations for pediatric regimens. - Estimating BSA-based doses for cytotoxic treatment protocols. - Checking the difference between a patient-specific dose and the reference adult dose. ## Frequently asked questions ### What formula does this calculator use? It uses the Mosteller formula: BSA (m²) = √(height in cm × weight in kg / 3600). ### What inputs are required? You must enter positive height, weight, and drug dose per m² values. Height is in cm, weight is in kg, and dose is in mg/m². ### How is the individualized dose calculated? The dose equals the entered drug dose per m² multiplied by the calculated BSA. ### What is the standard adult dose shown in the result? It is the dose calculated using the reference adult BSA of 1.73 m². ### Can this calculator be used for every drug? No. It is described for linear drug clearance models and does not apply to saturable, Michaelis-Menten pathways. It is not medical advice. ## Related tools - [A-a Gradient (Alveolar-Arterial O₂)](https://elysiatools.com/en/tools/a-a-gradient-calculator): Calculate the alveolar-arterial O₂ gradient to distinguish hypoxemia causes. PAO₂ = FiO₂×(P_atm−47) − PaCO₂/0.8; A-a = PAO₂ − PaO₂. Normal ≈ (Age+10)/4. Elevated → V/Q mismatch, shunt, diffusion impairment. Derived from StatPearls, LITFL, Cornell PICU, and Martin 1999. Not medical advice. - [Alveolar Gas Equation (PAO₂ Calculator)](https://elysiatools.com/en/tools/alveolar-gas-equation): Calculate PAO₂ = FiO₂ × (P_atm − 47) − PaCO₂ / RQ. Defaults: P_atm 760 mmHg (sea level), RQ 0.8. Gives a directional hint vs expected ~100 mmHg. For full A-a gradient interpretation use a-a-gradient-calculator. Derived from StatPearls, LITFL, Cornell PICU, and West. Not medical advice. - [Alveolar Ventilation Calculator (VA)](https://elysiatools.com/en/tools/alveolar-ventilation-calculator): Calculate VA = (VT − VD) × RR in L/min. VD may be supplied or estimated as ~2 mL/kg body weight. Normal resting ~4–6 L/min; low → hypercapnia, high → hypocapnia. Derived from West, LITFL, StatPearls, and Radford 1955. Not medical advice. - [Apgar Score (Newborn 1 & 5 min)](https://elysiatools.com/en/tools/apgar-score): Calculate the Apgar score to assess newborn condition at 1 minute and 5 minutes after birth. Five signs are each scored 0–2 at both time points: Appearance (skin color), Pulse (heart rate), Grimace (reflex irritability), Activity (muscle tone), and Respiration. Each time point totals 0–10. Interpretation: 7–10 reassuring; 4–6 moderately abnormal (may need assistance); 0–3 critically low (immediate resuscitation). The tool reports both the 1-min and 5-min scores, the change (delta), and per-time-point interpretation. A 5-min score, and especially the change from 1 to 5 min, indicates response to resuscitation; persistent low 5-min scores warrant continued resuscitation and reassessment at 10 min. Derived from Apgar 1953, reaffirmed by ACOG/AAP. The Apgar is a physiologic snapshot at a moment in time and is not, by itself, a marker of asphyxia or long-term neurologic outcome. Not medical advice. - [OD600 to CFU/mL Converter (Calibration Curve Slope)](https://elysiatools.com/en/tools/bacterial-growth-od): Convert OD600 to CFU/mL via a calibration slope with organism presets, blank correction, dilution handling, and linearity warnings. - [Henderson-Hasselbalch Equation (pH / HCO₃⁻ / PCO₂)](https://elysiatools.com/en/tools/bicarbonate-ph-conversion): Solve any one of pH/HCO₃⁻/PaCO₂ from the other two via pH = 6.1 + log10(HCO₃⁻/(0.03×PaCO₂)). Reports linear Henderson \[H⁺\] cross-check. Derived from Henderson 1908, Hasselbalch 1916, Siggaard-Andersen 1974, LITFL, StatPearls, Berend 2016. Not medical advice. - [Bilirubin Unit Converter (mg/dL ↔ µmol/L)](https://elysiatools.com/en/tools/bilirubin-unit-converter): Convert serum bilirubin (total/direct/indirect) between mg/dL and µmol/L. Factor 17.1 (molar mass 584.67 g/mol). Derived from Young 1987, StatPearls, AAP 2004, Bhutani. Not medical advice. - [Body Adiposity Index Calculator](https://elysiatools.com/en/tools/body-adiposity-calculator): Calculate Body Adiposity Index (BAI) - estimates body fat percentage from hip circumference and height ## Samples - [Web Image Processing Python Samples](https://elysiatools.com/en/samples/web-image-processing-python): Web Python image processing examples using PIL/Pillow including reading, saving, resizing, and format conversion - [Android Image Processing Java Samples](https://elysiatools.com/en/samples/android-image-processing-java): Android Java image processing examples including reading/saving images, scaling, and format conversion - [Android Image Processing Kotlin Samples](https://elysiatools.com/en/samples/android-image-processing-kotlin): Android Kotlin image processing examples including reading/saving images, scaling, and format conversion - [Web Image Processing Rust Samples](https://elysiatools.com/en/samples/web-image-processing-rust): Web Rust image processing examples including image read/save, scaling, and format conversion ## Related content - [Pharmacokinetic Teaching and Dose-Model Checks](https://elysiatools.com/en/hubs/pharmacokinetic-dose-planning-calculators): Explore pharmacokinetic formulas, model assumptions, and result consistency for teaching or QA without giving medication dosing or clinical advice.