Proper reinforcement is key to concrete durability. Our Rebar Spacing Calculator helps you determine the exact number of bars needed for your slab grid. Enter your slab dimensions, spacing requirements, and edge clearance to get a complete material list including total linear footage and estimated weight.
Calculate Rebar Spacing & Quantity
Estimate the number of rebar pieces, total length, and weight for your concrete slab grid. Supports custom spacing and clearance. Fast, free, and private.
About Calculate Rebar Spacing & Quantity
Slab Dimensions
Enter the length and width of your concrete slab.
Spacing & Size
Select your grid spacing (e.g., 16" OC) and rebar size.
Review Materials
See the total count of bars, linear feet, and weight.
Key Features
Grid Layout
Calculates bars for both length-wise and width-wise directions.
Weight Estimate
Provides estimated total weight based on rebar size (#3 to #8).
Custom Clearance
Adjust for edge clearance to ensure proper concrete cover.
Frequently Asked Questions
Common spacing is 12, 16, or 24 inches on center (OC), depending on the load requirements.
Rebar should typically be kept 2-3 inches away from the earth and edges to prevent corrosion.
No, this calculator determines the net length. You should add 10% extra for overlaps (splices) and waste.
Related Tools
View allLast updated on