Concrete Calculator
Estimate concrete volume, waste and bags.
Estimate concrete volume, waste and bags.
Estimate concrete volume, waste and bags. Fill in the fields above and the result updates instantly, together with the formula behind it.
Volume (m³) = length × width × thickness in meters × (1 + waste/100)
A 5 m × 4 m slab 10 cm deep needs 2 m³, or 2.2 m³ allowing 10% extra.
Length and width are meters; choose centimeters or inches for depth. Bag yield must come from the product label.
Volume (m³) = length × width × thickness in meters × (1 + waste/100). Example: A 5 m × 4 m slab 10 cm deep needs 2 m³, or 2.2 m³ allowing 10% extra.
You enter: Slab length (m); Slab width (m); Depth; Depth unit; Extra material (%); Concrete yield per bag (liters). An example value is shown in each empty field, and the result appears as soon as the numbers are valid.
Most guides suggest 5–10% extra to cover uneven ground, spillage and overdig. Set this in the extra-material field and round up to the next whole bag or delivery quantity.
Yes. Use Copy to copy the result or full example. Share creates a link that puts your chosen values into the URL fragment so another person can reproduce the calculation. Your named saves and recent history stay in your own browser.