Concrete Depot Concrete Calculators & Tools

Concrete Rebar Calculator

Estimate rebar inside concrete slabs, walls, footings, and foundations with cover, spacing, layers, lap allowance, weight, cost, and a clean report diagram.

Measurement inputs

Results update live when values change.

Project setup
Used in the PDF and saved report.
Switches starter units only.
10% is common for cut waste.
Rebar settings
Used for most bars in the selected mode.
For wall horizontal bars.
Used to estimate bars to buy.
Used only where a run needs a splice.
Used to draw and estimate weight.
Weight per unit length.
For custom bar only.
Cost settings
Optional. Use 0 to skip cost.
Choose how your price is quoted.
Full bars are used for buy count.
Slab dimensions
Enter a length greater than 0.
Enter a width greater than 0.
Enter a thickness greater than 0.
Slab rebar layout
Edge/surface cover.
Choose one-way or two-way rebar.
Double layer doubles grid length.
Spacing across slab width.
Spacing across slab length.
Wall dimensions
Enter a length greater than 0.
Enter a height greater than 0.
Enter a thickness greater than 0.
Wall rebar layout
Cover from faces and ends.
Double curtain uses front and back layers.
Optional starter bars.
Spacing across wall length.
Spacing up wall height.
Length of each dowel.
Footing dimensions
Enter a length greater than 0.
Enter a width greater than 0.
Enter a depth greater than 0.
Footing rebar layout
Side and bottom cover.
Used in labels and report.
Most footings use bottom bars.
Choose count or spacing.
Bars running lengthwise.
Across footing width.
Shown only when enabled.
Spacing along footing length.
Foundation dimensions
Enter a length greater than 0.
Enter a width greater than 0.
Enter a thickness greater than 0.
Foundation rebar layout
Edge, top, and bottom cover.
Used in report.
Double mat doubles grid length.
Spacing across foundation width.
Spacing across foundation length.
Adds perimeter bars.
Bars around perimeter.
Total rebar required Includes waste and lap allowance.
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