#5 Rebar — Diameter, Weight & Area
Deformed reinforcing bar per ASTM A615 / A706
#5 rebar (also written No. 5 or number 5 bar) is 5/8" — 0.625 inches (15.88 mm) — in nominal diameter; the "5" stands for 5/8 of an inch. It weighs 1.043 pounds per foot (1.552 kg/m) with a nominal cross-section of 0.31 in² (200 mm²). A standard 20 ft bar weighs 20.9 lb, a 40 ft bar 41.7 lb.
These nominal values (per ASTM A615) are what reinforcement schedules, quotes, and delivery tickets use — the deformations are already accounted for in the nominal diameter.
Size & Weight
| Nominal diameter | 0.625 in (15.88 mm) |
| Nominal area | 0.31 in² (200 mm²) |
| Weight | 1.043 lb/ft (1.552 kg/m) |
Ordering Numbers
| 20 ft bar | 20.9 lb |
| 40 ft bar | 41.7 lb |
| Bars per US ton (20 ft) | 95 |
Frequently Asked Questions
What is the diameter of #5 rebar?
5/8", i.e. 0.625 inches or 15.88 mm — bar numbers count eighths of an inch, so #5 is nominally 5/8".
How thick is #5 rebar?
Number 5 bar is 5/8" thick (15.88 mm). That is the nominal diameter: the ribs are already included, because the nominal size is defined by mass per foot.
How much does #5 rebar weigh per foot?
1.043 lb per foot (1.552 kg/m). A 20 ft bar weighs 20.9 lb; a US ton is about 95 such bars.
What is the area of #5 rebar?
The nominal cross-section of #5 is 0.31 in² (200 mm²) — the value reinforcement schedules use when summing required steel area.
What is the metric equivalent of #5 rebar?
The closest European size is Ø16 (16 mm, 1.58 kg/m, B500 per EN 10080). Matches are approximate — when substituting, match the required steel area, not the bar count.
What grade is #5 rebar?
Grade is independent of size: ASTM A615 Grade 40, 60, or 75 (yield in ksi), with Grade 60 the US default. A706 covers weldable low-alloy bars for seismic work.
Values are entered from the governing standard’s published tables and cross-checked programmatically against its mass and section formulas before publication. Spotted an error? Write to advertising@metalabout.net — verified corrections ship within days. About