Calculate the number of rebar pieces and total weight needed for your concrete slab, footing, or wall. Enter dimensions and bar spacing to get accurate estimates.
Enter Your Measurements
Results
Total Bars
42
pieces
Total Length
840
linear feet
Total Weight
561
lbs
Bars (Lengthwise)
21
pieces
Bars (Widthwise)
21
pieces
Formula
How to Use This Calculator
How to Use
- 1
Enter the length and width of the concrete area.
- 2
Enter rebar spacing in inches (12 inches is common for slabs).
- 3
Select the rebar size (number). #4 is most common for residential.
- 4
Results show total bars, linear feet, and weight.
Frequently Asked Questions
Frequently Asked Questions
What size rebar for a concrete slab?
How far apart should rebar be spaced?
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About This Calculator
This calculator uses the formula: Bars per direction = (Perpendicular dimension ÷ Spacing) + 1. All calculations follow industry-standard methods. Results are estimates — always verify with a licensed professional for structural or code-compliant work.
Built and maintained by the CalcSmart team. Last updated March 2026.
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