Sphere Surface Area
A sphere’s surface is 4πr², exactly four times the area of a circle with the same radius. Archimedes showed it also equals the lateral area of the cylinder that wraps it.
Your numbers
Surface area
1,256.64cm²
Volume
4,188.79cm³
Circumference
62.83cm
Formula
Surface area = 4 × π × Radius ²
For a given volume no shape has less surface than a sphere. That is why droplets and bubbles are round.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Radius (cm)Centre to edge — half the diameter. | 10 | 0 and up |
Step by step
Quick reference table
Results when only Radius (cm) changes and everything else stays put.
| Radius (cm) | Surface area (cm²) | Volume (cm³) | Circumference (cm) |
|---|---|---|---|
| 5 | 314.16 | 523.6 | 31.42 |
| 7.5 | 706.86 | 1,767.15 | 47.12 |
| 10 | 1,256.64 | 4,188.79 | 62.83 |
| 15 | 2,827.43 | 14,137.17 | 94.25 |
| 20 | 5,026.55 | 33,510.32 | 125.66 |
What each result means
| Result | At default values |
|---|---|
| Surface area (cm²)The total area of a solid’s outer skin. | 1,256.64 |
| Volume (cm³)The space a solid holds — length cubed. | 4,188.79 |
| Circumference (cm)The distance once around a circle. | 62.83 |
Common mistakes
For a given volume no shape has less surface than a sphere. That is why droplets and bubbles are round.
Glossary
- Radius
- Centre to edge — half the diameter.
- Surface area
- The total area of a solid’s outer skin.
- Volume
- The space a solid holds — length cubed.
- Circumference
- The distance once around a circle.
Frequently asked questions
Q. How is Sphere Surface Area calculated?
Surface area = 4 × π × Radius ² — A sphere’s surface is 4πr², exactly four times the area of a circle with the same radius. Archimedes showed it also equals the lateral area of the cylinder that wraps it.
Q. Can you walk through an example?
With Radius 10cm, the answer is Surface area 1,256.64cm².
Q. What do I need to enter?
Enter Radius. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Radius (cm) moves the answer to Radius (cm) 5 → Surface area (cm²) 314.16 and Radius (cm) 20 → Surface area (cm²) 5,026.55. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
For a given volume no shape has less surface than a sphere. That is why droplets and bubbles are round.
Related calculators
Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.