Building

Rebar Calculator

Estimate reinforcing-bar grid lines, linear feet and stock-bar quantity for rectangular slabs.

✓ No signup✓ Mobile friendly✓ Clear limitations✓ Browser-first where practical
Recent tools are remembered only on this device.
Planning estimate. Verify final quantities, local codes, manufacturer instructions and site conditions before purchasing materials or carrying out work.
52Grid lines total
1,375 ftRebar linear feet
69Stock bars
600 ft²Slab area

Why use this rebar calculator?

Rebar Calculator estimates a rectangular reinforcing grid from slab dimensions and bar spacing.

Example

For a 30 × 20 ft slab at 12-inch spacing, estimate total grid lines, linear feet and 20-ft stock bars.

Important note

Structural reinforcement size, spacing, cover, laps and detailing must follow the project design. This tool estimates quantity only.

How to use it

Start with the inputs shown above, review any options or assumptions, then generate the result. Where the tool creates a file, keep the original until you have opened and checked the downloaded output.

Frequently asked questions

Is this tool free?

Yes. The core tool is free to use.

Do I need an account?

No. You can use it without signing up.

Does it work on mobile?

Yes. Toolbox is designed for modern mobile and desktop browsers.