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Rebar weight and quantity calculator

Estimate nominal bar weight from an ASTM A615 bar size, single-bar length, and count.

Last reviewed: October 27, 2026

Inputs

ft

bars

Reinforcing bar diagram20 ft#3 bar

Results

Nominal unit weight
—
Total length
—
Total weight
—
Total short tons
—

Reference data: Nominal bar weights are from ASTM A615/A615M, Table 1. The project’s TODO_VERIFY.md lists this table for pre-launch verification.

How it works

Total length is bar length multiplied by quantity. Total weight is total length multiplied by the selected nominal unit weight.

Ltotal=nLbarL_{total}=nL_{bar}
Wtotal=Ltotal×wnominalW_{total}=L_{total}\times w_{nominal}

Assumptions and limitations

Weights are nominal ASTM A615 values and exclude hooks, laps, couplers, fabrication tolerances, coating, wire, chairs, waste, and delivery weight. Bar schedules and placing drawings govern quantity.

Worked example

Ten #4 bars at 20 ft each total 200 ft. At 0.668 lb/ft nominal weight, the estimated total is 133.6 lb, or 0.0668 short tons.

Frequently asked questions

Does this include lap splice length?
No. Enter the actual cut length from the approved bar schedule, including required laps and hooks.
Can I use the output for procurement?
Use it only as an estimate. Confirm supplier practices and the final bar list.

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Important disclaimer

For estimation and education, verify with a licensed engineer.