Skip to main content
R/FREE TOOLS

Rebar tools.

Schedule the bars, plan the cutting and check the weights. Built by the engineers who prepare bar bending schedules for contractors.
S-01/WEIGHT CALCULATORALL STANDARDS

Quick steel weight

Pick the standard on your drawings, then enter each bar size with the number of bars and the length of each.

  • 53.28 kg
Total steel

53.28 kg

= 0.053 tonnes

Nominal mass only. Add laps, hooks and wastage for an order quantity; rolling tolerance means delivered weight can differ slightly from nominal.

S-02/WEIGHT CHARTSBY STANDARD
S-03/COMPARISONMETRIC AND US BARS

The same bar across standards

Metric standards share nominal masses, so a 16 mm bar weighs the same under IS, BS and AS/NZS. US bars are sized in inches and never line up exactly: the nearest US size is shown for comparison, with its own weight.

Metric bar diameters across standards with the nearest US bar
Diameterkg/mIS 1786BS 4449AS/NZS 4671Nearest US barUS kg/m
6 mm0.2226 mm6 mm–#3 (9.5 mm)0.560
8 mm0.3958 mm8 mm–#3 (9.5 mm)0.560
10 mm0.61710 mm10 mmN10#3 (9.5 mm)0.560
12 mm0.88812 mm12 mmN12#4 (12.7 mm)0.994
16 mm1.57816 mm16 mmN16#5 (15.9 mm)1.552
20 mm2.46620 mm20 mmN20#6 (19.1 mm)2.235
24 mm3.551––N24#8 (25.4 mm)3.973
25 mm3.85325 mm25 mm–#8 (25.4 mm)3.973
28 mm4.83428 mm–N28#9 (28.7 mm)5.060
32 mm6.31332 mm32 mmN32#10 (32.3 mm)6.404
36 mm7.99036 mm–N36#11 (35.8 mm)7.907
40 mm9.86540 mm40 mmN40#14 (43 mm)11.380
50 mm15.413–50 mm–#14 (43 mm)11.380

Metric masses are calculated from nominal diameter at 7,850 kg/m³. US weights are the nominal values ASTM A615 defines for each size. See the ASTM A615 chart for weights in lb/ft.

S-04/QUESTIONS4

Mass in kg per metre = d² ÷ 162, where d is the bar diameter in millimetres. In US units, weight in lb per foot is about 2.67 × d² with d in inches. Both come from the bar's cross-sectional area multiplied by the density of steel (7,850 kg/m³, or 490 lb/ft³). Multiply by the total length of bars to get the weight.

Yes. IS 1786, BS 4449 and AS/NZS 4671 all define bars by nominal diameter, so a 12 mm bar has the same nominal mass, 0.888 kg/m, under each. Where the standards differ is in grades, ductility and tolerances.

No. A #4 bar is 1/2 inch, or 12.7 mm, and weighs 0.994 kg/m (0.668 lb/ft). A 12 mm bar weighs 0.888 kg/m, about 11% less. Converting a US schedule to metric bars, or the other way round, means selecting the bars again.

Charts give nominal mass. Bars are rolled within a mass tolerance set by each standard, so actual weight per metre varies slightly, and order quantities also carry laps, hooks and cutting wastage. Use nominal mass for estimates and the mill certificate or delivery ticket for actual weights.
ARCHED / ESTIMATING

Need the full bar bending schedule?

A weight chart gives you the steel for one bar. A schedule needs every bar on the drawings: shapes, cutting lengths, laps and the totals by size. Send the reinforcement drawings and we return the schedule in Excel, checked and signed off by an engineer.