Volume calculator

Concrete Volume Calculator

Enter concrete dimensions, subtract openings, and include waste before using the result.

Live modelMain slab · Box

Calculating

Shape

Main slab

2.4

Unit converter

Cubic volume unit converter

1 m³35.31 ft³
ft³35.31 ft³
yd³1.31 yd³
liters1,000 liters
US gal264.17 US gal
Project optionsUnits, material, cost, and waste
Output units
Cost estimate

How to use

How to calculate volume for your project

Switch between these options to match the way you are using the calculator right now.

Enter one shape and read the live total

  1. Choose the shape that matches the object you are measuring.
  2. Enter the required dimensions and confirm the input unit.
  3. Use the result panel to read cubic meters, cubic feet, liters, or gallons.

Start with the slab, footing, or column dimensions from the drawing.

Guide

Concrete volume calculator guide

Use this concrete volume calculator when the result needs to estimate the amount of concrete required from measured dimensions.

Concrete volume formula

Concrete volume is the sum of added pour sections minus subtracted openings or voids. A waste percentage can then be applied to the net volume.

Example concrete volume calculation

A slab is 20 ft long, 10 ft wide, and 0.5 ft thick.

20 x 10 x 0.5 / 27 = 3.7

The slab is about 3.7 yd3 before waste.

Unit notes

  • Concrete orders are often rounded after converting volume to yd3 or m3.
  • Use subtract mode for holes, sleeves, drains, or openings.
  • A waste factor accounts for site variation, spillage, and ordering margin.

Best uses

  • Slabs
  • Footings
  • Columns
  • Trenches
  • Openings and voids

Common mistakes

  • Using slab area without multiplying by thickness.
  • Entering inches of thickness as feet without conversion.
  • Forgetting to subtract large openings or voids.
How do I calculate concrete volume?

Calculate each concrete section from its dimensions, subtract voids, then apply any waste allowance needed for the project.

Why does concrete thickness matter?

Thickness is the third dimension that turns slab area into volume. Without thickness, the result is only area.

Can this concrete volume calculator subtract holes?

Yes. Add a component for the hole or void and set it to subtract from the total.

Should I include waste for concrete?

Usually yes for ordering. The right allowance depends on site conditions, supplier guidance, and project tolerance.

Is this concrete volume calculator structural advice?

No. It estimates quantity from dimensions. Structural design and safety decisions should be checked by a qualified professional.

This calculator provides estimates based on the dimensions and assumptions you enter. For engineering, structural, freight, or purchasing decisions, verify the result with a qualified professional or supplier.