Sphere Surface Area Calculator
Find the surface area of a sphere from its radius or diameter instantly with this free calculator that runs right in your browser.
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How to use this calculator
- Enter the radius.
- Press Calculate.
How it works
Surface area = 4 × π × radius².
Worked example
radius 1 m. ≈ 12.57 m².
Common mistakes
- Using the diameter as the radius — halve the diameter first.
- Confusing surface area (4πr²) with volume ((4/3)πr³).
Frequently asked questions
How do I find the surface area of a sphere?
Surface area = 4 × π × radius². For a 5 cm-radius sphere that is 4 × π × 25 ≈ 314 cm².
How does it relate to a circle?
A sphere's surface area is exactly four times the area of its great circle (πr²), a neat result from geometry.
How is surface area different from volume?
Surface area (4πr²) is the skin around the sphere in m²; volume ((4/3)πr³) is the space inside in m³.
Related tools
- Sphere Volume Calculator
- Circle Area Calculator
- Annulus Area Calculator
- Ellipse Area Calculator
- Equilateral Triangle Area Calculator
- Parallelogram Area Calculator
Explore more in Geometry, Shape, Area & Volume.
Cite this tool
Zerdly. (2026). Sphere Surface Area Calculator. Retrieved from https://www.zerdly.com/tools/sphere-surface-area-calculator/
Tip: Enter any known values to calculate the remaining results.
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