🧊 Volume Calculator

Volume of a cube, box, cylinder, cone, sphere, pyramid, prism, capsule, tube and more, with the formula shown and results in liters and gallons.

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Formula: V = π r² h

Volume of the cylinder
226.1947 in³
π × 3² × 8 = 226.1947 in³
UnitVolume
cubic inches226.1947
cubic feet0.1308997
cubic yards0.004848137
cubic centimeters (mL)3,706.667
liters3.706667
cubic meters0.003706667
U.S. fluid ounces125.3373
U.S. gallons0.9791977
Imperial gallons0.8153527

What Volume Calculator Does

This volume calculator finds the volume of twelve common solids — cube, rectangular box, cylinder, cone, sphere, hemisphere, rectangular pyramid, triangular prism, capsule, ellipsoid, truncated cone and hollow tube — and shows the formula with your measurements substituted. Enter dimensions in millimeters, centimeters, meters, inches, feet or yards, and tick “I measured the diameter” when that is easier than finding the radius.

The answer is converted into cubic inches, feet, yards, centimeters and meters, liters, U.S. fluid ounces, and U.S. and imperial gallons, so you can go straight from a tank’s measurements to how much water it holds.

How to Use Volume Calculator

  1. Choose a shape
  2. Pick the unit you measured in
  3. Enter each dimension — tick diameter if you measured across
  4. Read the volume with the formula and your numbers
  5. Use the table for liters, gallons and other cubic units

Formula Used by Volume Calculator

Cylinder

V = π r² h

Worked example

A tank 3 in radius, 8 in tall.

  1. π × 3² × 8 = 226.19 in³
  2. 226.19 ÷ 231

Result: 0.98 U.S. gallons.

Sphere

V = ⁴⁄₃ π r³

Worked example

A ball 10 cm across (r = 5 cm).

  1. ⁴⁄₃ × π × 125

Result: 523.6 cm³ = 0.524 liters.

Volume Unit Conversions

UnitEquals
1 liter1,000 cm³ = 33.81 U.S. fl oz
1 U.S. gallon231 in³ = 3.785 liters
1 imperial gallon4.546 liters
1 cubic foot1,728 in³ = 7.48 U.S. gallons = 28.32 liters
1 cubic yard27 ft³ = 764.6 liters
1 cubic meter1,000 liters = 264.2 U.S. gallons

How to Read Your Result

Why a cone is one third of a cylinder

A cone, and a pyramid, holds exactly one third of the prism or cylinder with the same base and height — a result known since ancient Greece. A sphere fits inside a cylinder of the same width and height and fills two thirds of it.

Inside vs outside measurements

For how much a container holds, measure the inside. For how much material it is made of — a pipe wall, a hollow tube — subtract the inner volume from the outer, which the tube shape does for you.

Limitations & Accuracy Notes

  • Shapes are ideal geometric solids; real containers have rounded corners, sloped sides and wall thickness.
  • Results are shown to about seven significant figures.

Frequently Asked Questions

How do you calculate volume?
Volume is the space inside a solid, in cubic units. For a box multiply length × width × height; for a cylinder π × radius² × height; for a sphere ⁴⁄₃ × π × radius³. Pick the shape and the calculator applies the formula and shows the working.
How do I find the volume of a cylinder?
V = π r² h. A can 3 inches in radius and 8 inches tall holds π × 9 × 8 ≈ 226.2 cubic inches, which is about 0.98 U.S. gallons. Tick “I measured the diameter” to enter the width directly.
How do I convert cubic units to liters or gallons?
One liter is 1,000 cubic centimeters; one U.S. gallon is 231 cubic inches (about 3.785 liters); one cubic foot is about 7.48 U.S. gallons. The results table converts automatically.
What is the volume of a cone compared with a cylinder?
Exactly one third of a cylinder with the same base and height: V = ⅓ π r² h. A pyramid is likewise one third of a box with the same base and height.
How do I find the volume of a pipe or tube?
Use the tube shape: V = π (R² − r²) h, the outer cylinder minus the hollow core. For the water a pipe holds, use a cylinder with the inner radius instead.
How do I calculate volume for concrete, soil or mulch?
Those are ordered by the cubic yard, so use the cubic yard, concrete or gravel calculators, which also handle depth in inches, waste allowance and bags.
By OnlineToolHubs Team • Updated September 2026