Sphere Radius from Surface Area Table: Radius by Surface area
Reference table of radius for Sphere Radius from Surface Area across a range of surface area values — exact, engine-computed figures you can read off at a glance.
Sphere Radius from Surface Area Calculator
Verified formula Updated Jun 2026 Private — runs on your device
Verified formula
Private
Radius
4.999998
- Diameter
- 10.0000
For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.
How to use the Sphere Radius from Surface Area Calculator
The Sphere Radius from Surface Area Calculator works out your radius, along with 1 related figure in an instant. Enter surface area and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.
- Enter the surface area.
- Read off your radius, together with diameter — the calculator updates automatically, with no button to press.
Formula
The Sphere Radius from Surface Area Calculator uses the formula:
Radius = √(Surface area ÷ (4 × 3.141592653589793))
Worked example
For example, with surface area of 314.159, the radius is 4.999998.
| Surface area | 314.159 |
|---|
| Radius | 4.999998 |
|---|---|
| Diameter | 10.0000 |
Results are estimates for educational use, not professional advice.
Key terms explained
- Surface area
- The total area of all the outer faces of a three-dimensional object.
- Diameter
- The distance across a circle through its centre — twice the radius.
- Radius
- The distance from the centre of a circle or sphere to its edge.
- Area
- The amount of two-dimensional space a shape covers, measured in square units.
Frequently asked questions
Divide the area by 4π and take the square root. A surface area of 314.16 gives a radius of 5.
Radius = √(area ÷ 4π), the inverse of the surface area formula 4πr².
Double the radius. The calculator shows both.
When you know a sphere's outer area, such as material to coat it, and need its size.
Enter the surface area. Read off your radius, together with diameter — the calculator updates automatically, with no button to press.
Related guides
How to Calculate Sphere Radius from Surface Area: Formula, Steps & Examples
Learn how to calculate Sphere Radius from Surface Area — the formula explained step by step, with worked examples and a free calculator to check your answer.