Surface Area Calculator
Box: 2(lw + wh + lh). Closed cylinder: 2πr(r + h). Sphere: 4πr².
Inputs and units
- Solid: Choose Rectangular box, Closed cylinder, Sphere.
- Length / radius: Enter your value in the format and unit shown.
- Width / height (ignored for sphere): Enter your value in the format and unit shown.
- Box depth (ignored for other shapes): Enter your value in the format and unit shown.
- Dimension unit: Choose Metres, Centimetres, Millimetres, Feet, Inches.
Calculation method
Box: 2(lw + wh + lh). Closed cylinder: 2πr(r + h). Sphere: 4πr².
Worked example
The example values are: Solid = box; Length / radius = 3; Width / height (ignored for sphere) = 4; Box depth (ignored for other shapes) = 5; Dimension unit = m
- Surface area (m²): 94
Assumptions and limitations
Check that the inputs and units describe your situation.
Using your result
Select Calculate after changing inputs. Copy result copies the displayed output; Download result saves a text file. Reset returns the form to its example inputs. Calculations run in your browser.
Surface Area Calculator FAQs
What method does this calculator use?
Box: 2(lw + wh + lh). Closed cylinder: 2πr(r + h). Sphere: 4πr².
What should I check before using the result?
Check that the inputs and units describe your situation.