Rebar Grid Estimator
Estimate rebar linear feet, bar count, and overlap allowance for a rectangular slab grid.
Limitations: Assumes a single rectangular grid. Chairs, ties, dowels, edge / bent / hooked bars, column starters, and mesh are not counted. For slab-on-grade only — structural slabs require engineered reinforcement.
What to do next: #4 bar (1/2-in) at 16 in OC is common for residential slabs. Minimum lap splice is typically 40× bar diameter (18–20 in for #4). Use chairs to keep bars mid-slab — rebar on the subgrade provides no benefit.
Planning estimate only. Structural reinforcement must follow the engineer-of-record drawings.