#4 rebar weight
0.668 lb/ft · 0.994 kg/m
#4 rebar has a nominal diameter of 12.7 mm (0.5 in) and a cross-sectional area of 127 mm².
#4 rebar weight calculator
Weight of standard bar lengths
| Bars | 20 ft (lb) | 40 ft (lb) | 60 ft (lb) |
|---|---|---|---|
| 1 | 13.4 | 26.7 | 40.1 |
| 10 | 133.6 | 267.2 | 400.8 |
| 50 | 668.0 | 1,336.0 | 2,004.0 |
| 100 | 1,336.0 | 2,672.0 | 4,008.0 |
Bars per ton
| Bar length | Bars per short ton (2000 lb) |
|---|---|
| 20 ft | 149.7 |
| 40 ft | 74.9 |
| 60 ft | 49.9 |
One short ton of #4 rebar is 2,994 ft per short ton. Use this to turn a weight on a delivery note into a bar count.
How the weight is calculated
Area = π ÷ 4 × 12.7² = 126.7 mm². Weight per metre = area × 7850 kg/m³ = 126.7 × 10⁻⁶ m² × 7850 = 0.994 kg/m. In US units: 0.500² × 2.67 = 0.668 lb/ft.
Deformed bars and TMT bars are sold by nominal diameter and nominal mass; the ribs are already allowed for, and standards accept a small mass tolerance per bar. See the rebar weight formula guide.
#4 rebar per square foot of slab
Weight of #4 rebar in a slab or wall for common spacings, for one layer in one direction and for bars both ways. Add laps, hooks and chairs on top.
| Spacing (centres) | One direction (lb/ft²) | Both directions (lb/ft²) |
|---|---|---|
| 4 in | 2.00 | 4.01 |
| 6 in | 1.34 | 2.67 |
| 8 in | 1.00 | 2.00 |
| 10 in | 0.80 | 1.60 |
| 12 in | 0.67 | 1.34 |
| 18 in | 0.45 | 0.89 |
Compared with nearby sizes
| Bar | lb/ft | kg/m | vs this bar |
|---|---|---|---|
| #3 rebar | 0.376 | 0.560 | −44 % |
| #4 rebar | 0.668 | 0.994 | — |
| #5 rebar | 1.043 | 1.552 | +56 % |
| #6 rebar | 1.502 | 2.235 | +125 % |
Bars of this size are typical for slab and wall reinforcement, footings of houses, lintels and stirrups in larger beams. The nearest metric bar is 12 mm rebar (12 mm, 0.888 kg/m); in soft metric sizes #4 rebar is called No.13.
Frequently asked questions
What is the weight of #4 rebar per foot?
#4 rebar weighs 0.668 lb/ft (0.994 kg/m).
How much does a 20 ft bar of #4 rebar weigh?
13.4 lb (0.668 lb/ft × 20 ft). A 40 ft bar weighs 26.7 lb.
How many 20 ft bars of #4 rebar are in a ton?
About 150 bars per short ton (2000 lb), or 2,994 ft per short ton.
What is the metric equivalent of #4 rebar?
The nearest metric bar is 12 mm rebar (12 mm, 0.888 kg/m). In soft metric designation #4 rebar is also called No.13; it is the same bar. Check the steel area in the design before substituting one for the other.
How is the weight of #4 rebar calculated?
Area = π ÷ 4 × 12.7² = 126.7 mm². Weight per metre = area × 7850 kg/m³ = 126.7 × 10⁻⁶ m² × 7850 = 0.994 kg/m. In US units: 0.500² × 2.67 = 0.668 lb/ft.
How much #4 rebar is needed per square foot at 12 in spacing?
One layer at 12 in centres needs 0.668 lb/ft² in one direction, 1.336 lb/ft² for bars both ways, plus laps.
Other bar sizes
#3 rebar · #5 rebar · #6 rebar · #7 rebar · #8 rebar · #9 rebar · #10 rebar · #11 rebar · #14 rebar · #18 rebar
Full rebar weight chart · Steel weight calculator
Data adapted from Wikipedia, "Rebar" (CC BY-SA 4.0).