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Sphere Radius from Volume Calculator.

Find a sphere's radius from its volume and report its surface area.

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01

Set your values

Results update as you type.

radius: 2.87941191

radius

2.87941191
surfaceArea: 104.18794157

surfaceArea

104.18794157

Results update automatically as you type.

Find a sphere's radius from its volume and report its surface area.

Use Cases

Reverse Engineering Sphere Dimensions

When you know the volume of a spherical object (like a tank or ball) but need its radius for design or fitting purposes.

Example: A spherical water tank holds 1000 liters. Find its radius to plan installation space.

Educational Math Practice

Students can verify their manual calculations for sphere radius from volume, reinforcing the relationship between volume and radius.

Example: Check your answer for a sphere with volume 904.32 cm³.

Frequently Asked Questions

How do I find the radius of a sphere if I know the volume?
Use the formula r = (3V / 4π)^(1/3), where V is the volume. Simply enter the volume into the calculator, and it will compute the radius for you.
What units should I use for the volume?
You can use any unit of volume (e.g., cubic meters, cubic centimeters, liters). The calculator will output the radius in the corresponding unit of length (e.g., meters, centimeters).
Can I use this calculator for a hemisphere?
No, this calculator is specifically for a full sphere. For a hemisphere, you would need to adjust the formula or use a different calculator.

Tips & Common Mistakes

Tips

  • Ensure the volume is entered in the correct unit. The radius will be in the cube root of that unit (e.g., m³ gives m).
  • If you have the diameter, remember that radius = diameter / 2. This calculator expects volume, not diameter.
  • For very large or small volumes, use scientific notation to avoid rounding errors.
  • Double-check that the volume is positive; a negative volume is not physically meaningful.

Common Mistakes to Avoid

  • Entering the diameter instead of the volume. This calculator only accepts volume input.
  • Forgetting to convert all measurements to the same unit system before entering the volume.
  • Using the formula for surface area instead of volume, leading to an incorrect radius.

Last updated: August 13, 2026