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Rebar weight Calculator

Calculate circular reinforcing bar weight with explicit lap lengths. This free rebar weight calculator shows the calculation and its assumptions so you can compare your own figures.

How the rebar weight calculation works

Mass per metre = π × diameter² ÷ 4 × density. Total length includes entered laps per bar.

Nominal circular area estimate. Lap and anchorage lengths must come from the structural design; this tool does not specify reinforcement.

Using this calculator

  1. Enter your own figures in the labelled inputs. Keep the currencies, units and time periods consistent.
  2. Choose any applicable rate profile, pattern or assumption shown for this tool. Open additional inputs when relevant.
  3. Review total weight kg and total length m, then read the stated assumptions and eligibility conditions before using the result.

Worked example

This is a static example using illustrative inputs, not facts about you or today’s date. The displayed eligibility selections and assumptions apply only to this example.

See example inputs
Bar diameter (mm)
12
Net bar length (m)
6
Number of bars
20
Added length per lap (m)
0.6
Laps per bar
1
Steel density (kg/m³)
7850
Total Weight Kg
117.19 kg
Total Length M
132 m
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