Free tool

Concrete Calculator for Slabs and Bags

Estimate concrete volume and bag counts for a simple slab. Enter dimensions and get a quick answer directly in your browser.

Calculate a slab

Unit system
ft
ft
in

Estimated concrete

Enter length, width, and thickness to calculate volume and bags.

This calculator treats imperial length and width as feet, imperial thickness as inches, metric length and width as meters, and metric thickness as centimeters. Results include a 10% waste allowance.

Runs entirely in your browser. Nothing is sent, stored, or logged.

Concrete Calculator Pro icon

Concrete Calculator Pro

Use Concrete Calculator Pro for saved project workflows, concrete volumes for slabs, walls, columns, and footings, and cost and bag-count estimation.

Concrete calculator questions

How is concrete volume calculated?

The tool multiplies length, width, and thickness, then converts the result into cubic yards and cubic meters with a 10% waste allowance.

Can I use metric measurements?

Yes. Use metric mode for length and width in meters and thickness in centimeters.

Are my measurements sent anywhere?

No. The calculator runs locally in your browser, and the measurements you enter are not sent, stored, or logged.

A free tool by NextTap. Runs entirely in your browser.