Volume Calculator
Pick a shape, enter its dimensions and get the volume in every common unit — from cubic inches to litres and gallons — with the formula written out.
- 12 shapes
- Metric and US units
- Formula shown
- Private
Step by step
How to calculate volume
Shape, unit, dimensions.
- 1
Choose the shape
Box, cylinder, sphere, cone, pyramid, tube and six more.
- 2
Pick the unit and enter the dimensions
Use the same unit of length for every dimension: millimetres to yards.
- 3
Read the volume
You get the volume in your unit cubed plus litres, cubic metres, cubic feet and gallons, along with the surface area.
From fish tanks to fuel tanks
Capacity, shipping, cooking, school and DIY.
Twelve solids
The shapes you actually meet: boxes, tanks, pipes, bowls, cones and tents.
Surface area too
Useful for paint, insulation, wrapping and material estimates.
All units at once
Litres, millilitres via cm³, cubic metres, cubic feet, cubic inches, cubic yards, US and UK gallons.
Formula and working
The formula, your numbers substituted and the result — ideal for checking homework.
Any unit of length
Enter in mm, cm, m, in, ft or yd; conversion is automatic.
Link to your calculation
Copy a link that reopens the calculator with your numbers filled in — handy for sharing or saving a scenario.
Made for phones
Large fields, the right keyboard for numbers and a layout that fits small screens.
Private by design
Everything is calculated in your browser. Your numbers are not sent to a server.
Volume formulas and unit conversions
Volume measures the space inside a solid. For shapes with straight sides it is base area × height: a box is length × width × height, a cylinder π × r² × h. Shapes that taper to a point hold one third of the matching straight shape — a cone is ⅓ × π × r² × h and a pyramid ⅓ × base area × height. A sphere is 4⁄3 × π × r³.
The key to correct results is consistent units. Measure every dimension in the same unit; the volume then comes out in that unit cubed. Because volume grows with the cube of length, conversions are larger than expected: 1 m³ is 1,000 litres or 1,000,000 cm³, and 1 cubic foot is 1,728 cubic inches.
For liquid capacity, remember that 1 litre equals 1,000 cm³ (a 10 cm cube) and that there are two gallons: the US gallon is 3.785 litres, the imperial (UK) gallon 4.546 litres. Use inside dimensions for tanks and containers, and measure the radius — half the diameter — for round shapes.
Volume formulas
| Shape | Volume | Variables |
|---|---|---|
| Box | l × w × h | length, width, height |
| Cylinder | π × r² × h | radius, height |
| Sphere | 4⁄3 × π × r³ | radius |
| Cone | ⅓ × π × r² × h | base radius, height |
| Pyramid | ⅓ × l × w × h | base length and width, height |
| Tube | π × (R² − r²) × h | outer and inner radius, length |
Tips
- Pouring a slab or footing? The Concrete Calculator adds waste and bag counts.
- Filling a bed or driveway with gravel, sand or soil? Use the Gravel Calculator to get the weight.
- Need a root, power or π in a formula of your own? Open the Scientific Calculator.
- To find the capacity of an irregular container, fill it with water from a measuring jug — or weigh it empty and full: 1 kg of water is 1 litre.
Frequently asked questions
Can’t find your answer? Contact us — we reply quickly.
How do I calculate the volume of a box?
Multiply length × width × height, all in the same unit. A 30 × 20 × 10 cm box holds 6,000 cm³, which is 6 litres.
How do I calculate the volume of a cylinder?
Multiply π by the radius squared and by the height: V = π × r² × h. With r = 5 cm and h = 10 cm the volume is about 785.4 cm³.
How many litres are in a cubic metre?
Exactly 1,000. One litre is one cubic decimetre (a cube of 10 cm), and a cubic metre contains 1,000 of them.
What is the difference between a US gallon and a UK gallon?
The US liquid gallon is 3.785 litres; the imperial gallon used in the UK is 4.546 litres, about 20 % larger.
How do I convert cubic feet to cubic yards?
Divide by 27, because a yard is 3 feet and 3 × 3 × 3 = 27. 54 ft³ is 2 yd³.
Are my numbers stored or sent anywhere?
No. The calculation runs in your browser. Your last inputs are remembered on your own device only, so the form is still filled in when you come back; use Reset to clear them.
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