Rebar Calculator
Calculate rebar quantity, spacing, and weight for slabs, footings, and walls. Includes lap splice lengths and total linear footage.
Length of the slab or footing in feet
Width of the slab or footing in feet
#4 at 12" OC is the standard residential spec. Use #5 or #6 for structural footings and grade beams.
On-center spacing between bars. 12" is standard for slabs, 6–8" for footings.
Overlap where bars connect. 24" is a common minimum — check your engineer's spec.
Adds a continuous bar around the perimeter of the slab for edge reinforcement
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