convertimate Rebar sizes

US bar number to millimeters

Type a value in # to get it in mm instantly.

15.88mm

That's 1.32× as thick as slab rebar, while footing rebar is 1.01× thicker. A bar that thick weighs 1.554 kg/m (1.044 lb/ft).

What it means

How thick is that bar?

Nominal diameters (ASTM A615). Weight for steel at 7,850 kg/m³; the deformations (ribs) are included in the nominal size.

The math

How to convert # to mm

Up to #8, diameter = number ÷ 8 in; #9–#18 by table. Weight = 0.006165 × d² kg/m (d in mm).

Example: #5 # = 15.875 mm.

Every unit

That bar in every unit

Tables

# to mm conversion table

# to mm conversion table
#mm
#3 #9.525 mm
#4 #12.7 mm
#5 #15.875 mm
#6 #19.05 mm
#7 #22.225 mm
#8 #25.4 mm
#9 #28.6512 mm
#10 #32.258 mm
#11 #35.814 mm
#14 #43.0022 mm
#18 #57.3278 mm
mm to # conversion table
mm to # conversion table
mm#
12.7 mm#4 #
15.9 mm#5 #
19 mm#6 #
22.2 mm#7 #
25.4 mm#8 #
28.7 mm#9 #
32.3 mm#10 #
35.8 mm#11 #
43 mm#14 #
57.3 mm#18 #

Quick answers

Quick answers

How many mm is #10 #?
#10 # is 32.258 mm.
How many mm is #5 #?
#5 # is 15.875 mm.

The units

About these units

US bar number (#)

US bar size #3 to #18.

Millimeters (mm)

Nominal diameter in millimeters.

Learn more about bar units

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