Free rebar weight and cost calculator. Select ASTM bar size or metric diameter, enter bar count, length, and steel price to estimate total rebar weight and material cost.
Determines reinforcing steel total weight and estimated material cost using standard ASTM bar sizes (#3–#11) or metric diameters (8mm–32mm).
W_{\text{total}} = N \times L \times w_{\text{unit}} \quad , \quad \text{Cost} = W_{\text{total}} \times \text{Price}
Imperial: total weight = number of bars × length per bar × the ASTM A615 standard unit weight for the selected bar size (#3–#11), e.g. #4 bar weighs 0.668 lb/ft. Metric: unit weight (kg/m) = diameter² ÷ 162.2, where diameter is in mm — this comes from the steel density of 7850 kg/m³. Your waste margin is added on top.
Enter the price your local supplier quotes per pound (US) or per kilogram. US retail rebar is often roughly $0.50–$0.90/lb depending on region, bar size, and quantity, and prices move with steel markets — confirm with a supplier before budgeting. Delivery, cutting, bending, tax, and lap-splice extras are not included.
No. Lap splice lengths and hooks must be added to your bar lengths before calculating — check the project drawings and specifications for the required lap lengths. The waste margin covers cutting waste only, not splices.
Calculations are preliminary estimates for planning and education. Verify results against project documents and applicable codes with a licensed Professional Engineer. The interactive calculator loads automatically when JavaScript is available.