Calculate the volume of boxes, rooms, tanks, cylinders, spheres, cones, pyramids, capsules, pipes and other common 3D shapes. Get results in cubic units, liters, US gallons and Imperial gallons.
Calculate Volume
Select a shape, choose your measurement unit and enter the dimensions. The calculator applies the appropriate geometric formula and converts the result into several useful volume units.
What This Volume Calculator Covers
How to Use the Volume Calculator
1. Select the shape
Choose the shape that most closely matches the object or space you are measuring. For example, use Rectangular Prism / Box for a concrete slab, room, foundation trench or rectangular container.
2. Choose your measurement unit
Select meters, centimeters, millimeters, feet, inches or yards. All dimensions entered into the calculator should use the selected unit.
3. Enter the dimensions
The required fields change automatically according to the selected shape. A cylinder needs radius and height, while a rectangular prism needs length, width and height.
4. Calculate the volume
Select Calculate Volume. The calculator displays the primary result, converted units, formula and step-by-step calculation.
5. Check the converted results
The result includes cubic meters, cubic feet, liters and US gallons. These conversions help when the calculation is being used for construction, tanks, water storage or material quantities.
Volume Formulas
Volume measures the three-dimensional space occupied by a solid or contained within a vessel. Each shape uses its corresponding geometric formula.
| Shape | Formula | Common Applications |
|---|---|---|
| Rectangular prism | V = L x W x H | Rooms, slabs, boxes, foundations and tanks |
| Cube | V = a³ | Equal-sided blocks and cubic spaces |
| Cylinder | V = pi x r² x h | Round tanks, columns and pipes |
| Sphere | V = (4/3) x pi x r³ | Spherical tanks and objects |
| Cone | V = (1/3) x pi x r² x h | Conical piles, funnels and tapered forms |
| Hemisphere | V = (2/3) x pi x r³ | Domes and half-spherical objects |
| Square pyramid | V = (1/3) x a² x h | Pyramidal structures and geometry |
| Triangular prism | V = (1/2) x b x h x L | Triangular beams and sections |
| Conical frustum | V = (1/3) x pi x h x (R² + Rr + r²) | Tapered tanks, buckets and truncated cones |
| Capsule | V = pi x r² x h + (4/3) x pi x r³ | Rounded tanks and capsule-shaped objects |
| Ellipsoid | V = (4/3) x pi x a x b x c | Oval and stretched spherical objects |
| Hollow tube | V = pi x (D² - d²) x L / 4 | Pipes and hollow cylindrical sections |
Common Volume Conversions
| Unit | Equivalent |
|---|---|
| 1 cubic meter | 1,000 liters |
| 1 cubic meter | 35.3147 cubic feet |
| 1 cubic meter | 264.172 US gallons |
| 1 cubic foot | 28.3168 liters |
| 1 cubic foot | 7.48052 US gallons |
| 1 US gallon | 3.78541 liters |
| 1 cubic yard | 27 cubic feet |
| 1 cubic yard | 0.764555 cubic meters |
| 1 liter | 1,000 cubic centimeters |
US gallon conversions use the US liquid gallon. Imperial gallons are different and should not be substituted for US gallons.
Volume Calculator for Construction
Volume calculations are common in construction estimating. A rectangular prism formula works for many basic quantities, including concrete slabs, footings, walls, beams and excavation spaces.
Concrete volume
For a rectangular concrete element, multiply length by width by thickness. Keep all three dimensions in the same unit before calculating.
For larger construction quantities, convert the final volume to cubic feet, cubic yards or cubic meters depending on the material supplier's measurement system.
Round columns and cylindrical elements
Use the cylinder option for circular columns and similar elements. Remember that the cylinder formula requires the radius, not the diameter. If you only know the diameter, divide it by 2 before entering the radius.
Volume Calculator for Tanks and Containers
For a tank or container, use the internal dimensions when you need its capacity. The rectangular tank mode also accepts a fill depth so you can calculate the volume of liquid currently inside the tank.
Rectangular tank
A rectangular tank uses: Volume = length x width x liquid depth.
Round tank
A vertical cylindrical tank uses: Volume = pi x radius² x height.
Why partial tank volume matters
A container's total capacity and its current contents are different measurements. Enter the liquid level rather than the full tank height when you need the amount currently inside a rectangular tank.
Important Volume Calculation Tips
Frequently Asked Questions
What is the formula for volume?
The formula depends on the shape. A rectangular prism uses length x width x height, while a cylinder uses pi x radius² x height.
How do I calculate the volume of a rectangular room?
Multiply the room's length by its width and ceiling height. The result is the room volume in cubic units matching the dimensions you entered.
How do I calculate cylinder volume?
Multiply pi by the square of the radius and then multiply by the cylinder's height. Use half the diameter as the radius.
How do I calculate volume from diameter?
For circular shapes, divide the diameter by 2 to obtain the radius before applying the volume formula.
How many liters are in a cubic meter?
One cubic meter equals 1,000 liters.
How many gallons are in a cubic foot?
One cubic foot is approximately 7.48052 US gallons.
How do I calculate concrete volume?
For a rectangular concrete element, multiply length by width by thickness. Convert the result to the unit used for purchasing or estimating the concrete.
How do I calculate tank capacity?
Select the tank's geometric shape and enter its internal dimensions. For a partially filled rectangular tank, use the fill depth instead of the total tank height.
What if the object has an irregular shape?
Divide the object into simpler geometric sections. Calculate each section separately and add or subtract the resulting volumes.
What is the difference between volume and capacity?
Volume describes three-dimensional space. Capacity usually describes how much a container can hold. For containers, internal volume is normally the useful capacity measurement.
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References and Methodology
The calculator uses standard geometric volume formulas for the supported shapes. Unit conversions follow established SI and US customary conversion factors. The calculator is intended for measurement, estimating, education and general planning. For critical engineering or structural quantities, verify dimensions and project-specific requirements before ordering materials or making construction decisions.
- NIST Guide to the SI, Appendix B, conversion factors.
- Standard geometric volume relationships for common three-dimensional solids.
- Geometric measurement principles for rectangular, cylindrical, spherical and tapered forms.
