Rebar Calculator

Figure out how much rebar a concrete slab needs. Set the grid spacing and bar size to get bar counts, total length, and weight for the whole pour.

ft
ft
in
in
Clear cover from slab edge to first bar.

📏 Grid math

Counts full bars in both directions from a 3 in edge offset.

⚒️ Laps included

Adds a waste factor for bar laps and cut pieces.

💾 Weight

Uses standard ASTM rebar weights per foot.

🔒 Private

All calculations run locally in your browser.

More construction tools

Pour it once, pour it right.

Concrete Calculator → Gravel Sand

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