Online Tool Store
Volume Calculator
Calculate the volume of 8 solids from their dimensions, with the formula shown and results converted to litres and US gallons. Runs entirely in your browser.
This works right here on your device — nothing gets sent out.
How it works
- Choose a solid — cube, box, sphere, hemisphere, cylinder, cone, square pyramid, or triangular prism.
- Pick the unit your dimensions are measured in, from millimetres to yards.
- Fill in the dimensions shown for that shape.
- The volume updates instantly in your chosen unit cubed, with the formula used and the litre/US gallon equivalent shown underneath, plus a copy button for the result.
Each shape uses its standard geometric volume formula: a cube is side³, a box is length × width × height, a sphere is (4/3)πr³, a hemisphere is (2/3)πr³, a cylinder is πr²h, a cone is (1/3)πr²h, a square pyramid is (1/3) × base² × height, and a triangular prism is (1/2) × triangle base × triangle height × prism length. The calculator plugs your numbers straight into the matching formula.
FAQ
Which solids does this cover?
Cube, rectangular prism (box), sphere, hemisphere, cylinder, cone, square pyramid, and triangular prism — the eight 3D solids that come up most often in geometry classes and everyday measuring.
What units does the result use?
Pick a dimension unit (millimetres through yards) and every field is measured in it; the volume is shown in that unit cubed. The result also converts automatically to litres and US gallons, so you don't need a separate unit converter for tank or container sizing.
How do I convert the volume to litres or gallons?
You don't have to — it's automatic. Once you enter dimensions, the result shows the volume in your chosen unit cubed plus its equivalent in litres and US gallons underneath.
Why does the cone use 1/3 but the cylinder doesn't?
A cone is exactly one-third the volume of a cylinder with the same base radius and height — you can verify this by filling a cone-shaped container with water three times into a same-sized cylinder. The same 1/3 factor applies to a pyramid versus a prism with the same base and height.
Is anything I enter sent anywhere?
No. Every calculation happens locally in your browser with plain arithmetic — nothing is uploaded or logged.
Can I use decimals?
Yes — every dimension field accepts decimals, so measurements like 4.5 or 2.75 work exactly as typed.
How we compare
| Feature | Online Tool Store | Doing it by hand | Generic calculator app |
|---|---|---|---|
| No file upload — runs in your browser | ✓ | ✓ | ✓ |
| No formula to remember or π to look up | ✓ | Manual recall required | Still need the right formula |
| Eight solids in one tool, formula shown | ✓ | Only what you remember | Usually just a number, no formula |
| Automatic litre and US gallon conversion | ✓ | Separate conversion needed | Usually not included |
| One-click copy of the result | ✓ | Manual retyping | Usually not included |
Doing it by hand risks a slipped digit or the wrong formula, and most generic calculator apps only handle one shape at a time with no working shown and no unit conversion. Volume Calculator switches formulas automatically when you change shape, lets you pick the dimension unit, and always shows the arithmetic plus the litre/US gallon equivalent behind the result.