Body Surface Area Calculator

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Calculate body surface area with the Du Bois and Mosteller formulas used for clinical dosing.

Inputs

Weight (kg)

Height (cm)

How to use this calculator: Body Surface Area Calculator

Calculate body surface area with the Du Bois and Mosteller formulas used for clinical dosing. The example below is calculated by this page's real engine from the displayed inputs.

1Confirm that the Body Surface Area Calculator matches the quantity or design check you need.
2Enter Weight and Height using the units printed beside each field.
3Check every value before calculating, especially decimal points and measurement units.
4Calculate, then follow the substituted equations in the worked example and compare the result with any stated limit.
5Read the assumptions, warnings and cited references before using the result for a financial, medical or engineering decision.

Input guide and example values

Use values from the same measurement basis and time period. Conditional fields appear only when the related option is selected.

Input	Example value	Why it matters
Weight	70 kg	Measured or known weight used by the calculation engine.
Height	172 cm	Measured or known height used by the calculation engine.

Formula inputs & variables for Body Surface Area Calculator

These are the named quantities used by this calculator. When the source formula does not define a mathematical symbol, OneCalcApp keeps the real input label instead of inventing one.

Variable / input	Unit	Meaning in this calculation
Weight	kg	Measured or known weight used by the calculation engine.
Height	cm	Measured or known height used by the calculation engine.

How the Body Surface Area Calculator works

The Body Surface Area Calculator uses Weight and Height to calculate BSA (Mosteller), BSA (Du Bois), and Average. Its engine applies Mosteller: √(h × w / 3600); the worked values below come from that same live calculation rather than a separately typed example.

With Weight 70 kg and Height 172 cm, the main worked-example result is BSA (Mosteller) = 1.83 m².

How each Body Surface Area Calculator input is used

Weight

The Body Surface Area Calculator worked example uses Weight = 70 kg. This value is passed directly into the calculation, with an allowed minimum 0.

Height

The Body Surface Area Calculator worked example uses Height = 172 cm. This value is passed directly into the calculation, with an allowed minimum 0.

Body Surface Area Calculator formulas and result interpretation

Formula 1: relationship used

In the Body Surface Area Calculator, Mosteller: √(h × w / 3600). The quantities in this relationship come from the named inputs or from an earlier calculation step shown in the worked example.

Formula 2: relationship used

In the Body Surface Area Calculator, Du Bois: 0.007184 × h^0.725 × w^0.425. The quantities in this relationship come from the named inputs or from an earlier calculation step shown in the worked example.

BSA (Mosteller)

For the displayed Body Surface Area Calculator worked example, BSA (Mosteller) is 1.83 m². Verify Weight and Height and their units before relying on this output.

BSA (Du Bois)

For the displayed Body Surface Area Calculator worked example, BSA (Du Bois) is 1.83 m². Verify Weight and Height and their units before relying on this output.

Average

For the displayed Body Surface Area Calculator worked example, Average is 1.83 m². Verify Weight and Height and their units before relying on this output.

Body Surface Area Calculator accuracy, checks and limitations

Body Surface Area Calculator units check: confirm Weight (kg) and Height (cm) before calculating.
Body Surface Area Calculator result check: compare BSA (Mosteller), BSA (Du Bois), and Average with the substituted formula steps and the displayed rounding precision.
Body Surface Area Calculator: This is a general estimate, not a diagnosis or personal medical advice. Discuss health decisions with a qualified clinician.

Formula, derivation and worked example

BSA scales better than body weight for many drug doses and for cardiac output, which is why hospitals use it. Mosteller is the simple square-root version; Du Bois is the older reference standard.

Mosteller: √(h × w / 3600)

Du Bois: 0.007184 × h^0.725 × w^0.425

Substitution steps

1. Mosteller
√(h·w/3600)
= 1.83 m²

Computed example results

BSA (Mosteller): 1.83 m²
BSA (Du Bois): 1.83 m²
Average: 1.83 m²

Understanding the result

Read the main result together with supporting checks, assumptions, limits and intermediate values.

For a manual check, repeat the first equation, confirm the units and change one input at a time.

Assumptions and calculation scope

Weight is assumed to be entered in kg; converting from another unit before entry avoids changing the numerical meaning of the calculation.
Body Surface Area Calculator applies the displayed Mosteller: √(h × w / 3600) relationship to the entered health inputs. Factors that are not exposed as inputs or stated assumptions are outside this calculator's calculation scope.

Common mistakes when using Body Surface Area Calculator

Do not mix units for Weight (kg), Height (cm). A unit mismatch changes the input magnitude even when the typed number looks reasonable.
Do not replace the displayed Mosteller: √(h × w / 3600) relationship with a different convention without also changing the underlying assumptions; compare like-for-like methods when checking the result.
Do not treat BSA (Mosteller) = 1.83 m² from the worked example as a universal answer. It belongs to the displayed example inputs and must be recalculated for the actual case.

When the Body Surface Area Calculator is useful

Body Surface Area Calculator is designed for cases where Weight, Height are known and you need BSA (Mosteller), BSA (Du Bois), Average. The page keeps the live calculator, calculation method and worked example together so the result can be checked instead of treated as a black-box number.

Use the calculator for the scope described by its inputs and notes. The displayed method is Mosteller: √(h × w / 3600). If the real project or decision needs factors that are not represented here, treat the result as an estimate and add the missing checks separately.

Weight and Height: what changes the answer

The worked example uses Weight = 70 kg, Height = 172 cm. With those values, BSA (Mosteller) is 1.83 m². Changing an input should be interpreted according to that field's unit, range, option and hint rather than by the number alone.

For this calculator, the main input roles are: Weight (kg): Measured or known weight used by the calculation engine. Height (cm): Measured or known height used by the calculation engine.

How to sanity-check a Body Surface Area Calculator result

Start by confirming the entered values and units, then compare the substituted working with the displayed formula or calculation steps. Pay particular attention to BSA (Mosteller), because it is the first worked-example output shown by the live engine.

Finally, compare the result with the assumptions, warnings and related calculators on this page. A nearby calculator can be useful as a cross-check when it measures the same workflow from a different input or output direction.

Next logical calculator

Continue with BMI Calculator

Useful next check because both tools use Weight and Height, while BMI Calculator answers a different part of the same workflow.

Open BMI Calculator

Formula

Mosteller: √(h × w / 3600)
Du Bois: 0.007184 × h^0.725 × w^0.425

BSA scales better than body weight for many drug doses and for cardiac output, which is why hospitals use it. Mosteller is the simple square-root version; Du Bois is the older reference standard.

Frequently asked questions

What inputs does the Body Surface Area Calculator use?

It uses Weight and Height. Follow the unit printed for each field and choose any selectable option to match the real scenario.

What does the Body Surface Area Calculator calculate?

It calculates BSA (Mosteller), BSA (Du Bois), and Average. With the displayed default inputs, BSA (Mosteller) is 1.83 m².

Which formula does the Body Surface Area Calculator use?

The primary relationship is Mosteller: √(h × w / 3600). The page also shows substituted values and calculation steps so the result can be checked independently.

How can I verify a Body Surface Area Calculator result?

First verify the units for Weight and Height. Then compare the substituted formula steps with BSA (Mosteller) and its displayed precision.

What are the limitations of the Body Surface Area Calculator?

Body Surface Area Calculator: This is a general estimate, not a diagnosis or personal medical advice. Discuss health decisions with a qualified clinician.

Where can I find related Health tools?

Use the related-tools section on this page to compare another method, change units or continue the same health calculation.

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