#5 rebar has a nominal diameter of 5/8 inch (0.625″) and weighs 1.043 pounds per foot — a standard 20-foot stick weighs about 20.9 lb. The size number is the diameter in eighths of an inch. #5 is typically used for footings, foundation walls, structural slabs, retaining walls. The calculator above is pre-set to #5; enter your slab size and spacing to get sticks and total weight.
| Size | Diameter | Weight | Metric |
|---|---|---|---|
| #3 | 0.375″ | 0.376 lb/ft | 0.56 kg/m |
| #4 | 0.500″ | 0.668 lb/ft | 0.99 kg/m |
| #5 | 0.625″ | 1.043 lb/ft | 1.55 kg/m |
| #6 | 0.750″ | 1.502 lb/ft | 2.23 kg/m |
| #7 | 0.875″ | 2.044 lb/ft | 3.04 kg/m |
| #8 | 1.000″ | 2.67 lb/ft | 3.97 kg/m |
| #9 | 1.128″ | 3.4 lb/ft | 5.06 kg/m |
| #10 | 1.270″ | 4.303 lb/ft | 6.4 kg/m |
| #11 | 1.410″ | 5.313 lb/ft | 7.91 kg/m |
Common questions
What diameter is #5 rebar?
5/8 inch nominal (0.625"). US rebar sizes count eighths of an inch of diameter, so a #5 bar is 5/8" thick.
How much does #5 rebar weigh?
1.043 lb per foot — about 20.9 lb per standard 20-ft stick. Total weight matters because suppliers price larger orders by weight, and it tells you whether your truck can haul it.
What is #5 rebar used for?
Commonly footings, foundation walls, structural slabs, retaining walls. Bar size and spacing are structural decisions — follow your plans or local code, not a calculator, for anything load-bearing.