Millimeters to US bar number
Type a value in mm to get it in # instantly.
#5#
That's 1.33× as thick as slab rebar, while footing rebar is 1.01× thicker. A bar that thick weighs 1.559 kg/m (1.047 lb/ft).
Convert the other way: # to mm
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 mm to #
Up to #8, diameter = number ÷ 8 in; #9–#18 by table. Weight = 0.006165 × d² kg/m (d in mm).
Example: 15.9 mm = #5 #.
Every unit
That bar in every unit
Tables
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 # |
# 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 |
Quick answers
Quick answers
- How many # is 10 mm?
- 10 mm is #3 #.
- How many # is 15.9 mm?
- 15.9 mm is #5 #.
The units
About these units
Millimeters (mm)
Nominal diameter in millimeters.
US bar number (#)
US bar size #3 to #18.
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