Surface Area of a Sphere Calculator
Result
Surface Area of a Sphere Calculator Calculate the surface area of a sphere from its radius using A = 4πr². A sphere is the set of all points at distance r from a centre, and its outer skin has area exactly four times that of a flat circle of the same radi — free online calculator.
Formula
- Surface Area of a Sphere Calculator finds the total outer area of a sphere from its radius using A = 4πr².
- The main inputs are Radius. Enter them in the units and format shown in the calculator.
- Keep comparable quantities in compatible units whenever the formula combines or compares them.
- Changing any input above recalculates the result with the same calculation engine used by this page.
Example: Surface Area of a Sphere
- Radius: 3 units
For r = 3, A = 4π × 3² = 36π ≈ 113.10 square units.
Sample result: Calculating…
Frequently asked questions
What does the Surface Area of a Sphere calculate?
Surface area depends on the square of the sphere radius.
Which values should I enter?
Enter Radius using the units and format shown beside each field.
What formula does this calculator use?
The calculator uses the following relationship: A = 4πr².
Why might my result differ from another source?
Results can differ when another source uses different units, rounding rules, conventions or assumptions. Compare the inputs and definitions before comparing results.
Does the result update automatically?
Yes. Changing an input updates the result using the same calculation engine shown on this page.