Volume calculator
Pick a shape, enter its dimensions in mm, cm, m, in, ft or yd and get the volume in m³, litres, cm³, ft³, yd³ and US/UK gallons — with the formula worked out using your numbers.
Defaults to your region. Switch to compare any other scale.
1 in = 0.0254 m, 1 ft = 0.3048 m, 1 yd = 0.9144 m exactly; 1 L = 0.001 m³; 1 US gal = 3.785411784 L; 1 UK gal = 4.54609 L.
Result
3 m³
Volume — Rectangular box (cuboid)
= 3,000 L · 105.944 ft³ · 792.5162 US gal
- Step 1 — formulaV = l × w × h
- Step 2 — insert your numbersV = 2 m × 1.5 m × 1 m
- Step 3 — volume in your unitV = 3 m³
- Step 4 — convert to m³3 m³
- Litres3,000 L
- Cubic centimetres3,000,000 cm³
- Cubic feet105.944 ft³
- Cubic yards3.9239 yd³
- US gallons792.5162 US gal
- UK (imperial) gallons659.9077 UK gal
What this volume means
Rectangular box (cuboid): 3 m³ holds 3,000 litres of liquid (1 m³ = 1000 L). For concrete or soil, order by m³ (or yd³ in the US); for water, read the litres or gallons.
Volume in every unit
| Unit | Symbol | Value |
|---|---|---|
| Cubic metres | m³ | 3 |
| Litres | L | 3,000 |
| Cubic centimetres | cm³ | 3,000,000 |
| Cubic feet | ft³ | 105.944 |
| Cubic yards | yd³ | 3.9239 |
| US gallons | US gal | 792.5162 |
| UK (imperial) gallons | UK gal | 659.9077 |
About this tool
Volume is the space a solid takes up, measured in cubic units. Every shape has its own formula: a box is length × width × height, a cylinder is π × r² × h, a sphere is 4/3 × π × r³, and a cone or pyramid is exactly one third of the matching cylinder or box. A frustum (truncated cone, like a bucket) uses 1/3 × π × h × (R² + R·r + r²); a pipe or hollow cylinder subtracts the inner cylinder from the outer one; a capsule adds a sphere to a cylinder.
The calculator works in the unit you type, then converts the cubic result to cubic metres with exact international factors (1 in = 2.54 cm, 1 ft = 30.48 cm, 1 yd = 91.44 cm), so 1 ft³ = 0.028316846592 m³. From cubic metres it shows litres (1 m³ = 1000 L), US gallons (3.785411784 L) and UK gallons (4.54609 L).
Two practical presets save time: the pool/tank preset averages the shallow and deep end, and the concrete preset adds a waste or spare percentage (5–10% is common) so you order enough ready-mix. Need to change units of a volume you already know? Use the volume converter.
Formula
V_cube = a³V_box = l × w × hV_cylinder = π r² hV_sphere = 4/3 π r³V_hemisphere = 2/3 π r³V_cone = 1/3 π r² hV_frustum = 1/3 π h (R² + R r + r²)V_pyramid = 1/3 l w hV_prism = 1/2 b hₜ lV_capsule = π r² h + 4/3 π r³V_ellipsoid = 4/3 π a b cV_tube = π (R² − r²) hV_pool = l w (d₁ + d₂)/2V_concrete = l w t (1 + waste%)V(m³) = V(cm³) × 0.01³ = V(ft³) × 0.3048³ = V(in³) × 0.0254³
How it is calculated
- Choose the shape (or the pool / concrete preset).
- Pick the length unit and enter the dimensions shown for that shape.
- The calculator writes the formula, then the same formula with your numbers.
- It multiplies out the volume in your unit cubed and converts it to m³ with the exact factor.
- Read the result in m³, litres, cm³, ft³, yd³ and US / UK gallons.
Questions
How do I calculate the volume of a cylinder?
Multiply the area of the circular base by the height: V = π × r² × h. Example: r = 0.5 m, h = 2 m → π × 0.25 × 2 ≈ 1.5708 m³ ≈ 1570.8 litres. If you know the diameter, halve it first to get the radius.
How many litres are in a cubic metre?
Exactly 1000 litres. One litre is one cubic decimetre (10 cm × 10 cm × 10 cm), and 1 m³ = 10 × 10 × 10 dm³. So 1 cm³ = 1 mL.
How do I work out pool volume in litres?
For a rectangular pool use length × width × average depth, where average depth = (shallow + deep) / 2. A 10 × 4 m pool from 1.2 m to 2 m holds 10 × 4 × 1.6 = 64 m³ = 64 000 litres. For a round pool choose the cylinder.
How much concrete do I need for a slab?
Multiply length × width × thickness in the same unit, then add 5–10% for spillage and uneven ground. A 5 × 4 m slab, 10 cm thick, is 2 m³; with 5% spare order 2.1 m³ (≈ 2.75 yd³).
Why is a cone one third of a cylinder?
Any solid that narrows linearly from a base to a point (cone or pyramid) has exactly 1/3 of the volume of the prism or cylinder with the same base and height — a result of integrating the shrinking cross-section. So V_cone = 1/3 × π r² h and V_pyramid = 1/3 × l × w × h.