Rebar sizes #3 to #6, rod chairs and rebar caps

Rebar: what we stock

Rebar size chart

These are the nominal dimensions ASTM A615 sets for deformed carbon-steel bar. Every US mill rolls to the same numbers, so a #4 bar weighs the same per foot whatever the brand or grade. We list #7 and #8 for reference; Yankocy stocks #3 through #6.

Nominal diameter is the diameter of a plain round bar with the same weight per foot. The ribs make the bar measure slightly larger across.

How much does a piece of rebar weigh?

Multiply the weight per foot by the length. These are the lengths and bundle counts Yankocy stocks.

How do you read rebar bar marks?

Rolled into each bar is a short code. First comes the mill's letter or symbol, then the bar size, then the steel type: S for carbon steel to ASTM A615, W for low-alloy weldable steel to ASTM A706. Last is the grade, shown as a number such as 60, or as one extra line along the bar for Grade 60.

The grade sets minimum yield strength. Under A615, Grade 60 bar yields at 60,000 psi or more, and Grade 40 bar is only made in sizes #3 through #6. Our #3 bar is Grade 40, the bar pool builders use most; our #4, #5 and #6 bar is Grade 60.

Rod chairs and rebar caps

Rod chairs hold bar off the subgrade or form so it sits at the right depth once the concrete is placed. We stock 2-piece and 3-piece chairs. For slab bolsters, see our masonry supply line.

OSHA 1926.701(b) requires protruding reinforcing steel that workers could fall onto to be guarded against impalement. Yankocy stocks high-visibility orange safety caps and 4x4 OSHA-approved caps that fit 3/8" to 1" bar.

What to order with rebar

• 6x6 re-mesh sheets or rolls for slab-on-grade crack control
• Dura-Wall block mesh for the bed joints of block walls
• Sonotube forms for piers and column footings
• Rod chairs and safety caps sized to the bar

Questions about rebar

Is #4 rebar 1/2 inch?

Yes. Rebar size numbers count eighths of an inch, so #4 is 4/8" or 1/2" nominal diameter. It weighs 0.668 lb per foot and has a 0.20 sq in cross-section. Yankocy stocks Grade 60 #4 in 10' and 20' lengths, 150 bars per bundle.

Is #4 rebar bigger than #6?

No. The higher the number, the larger the bar. #6 rebar is 3/4" in diameter and weighs 1.502 lb per foot, more than twice the 0.668 lb per foot of 1/2" #4 bar.

Is #3 rebar smaller than #4?

Yes. #3 rebar is 3/8" in diameter and weighs 0.376 lb per foot. #4 is 1/2" and 0.668 lb per foot. Its cross-section is 0.11 sq in, against 0.20 sq in for #4. Yankocy stocks both in 10' and 20' lengths: #3 in Grade 40, #4 in Grade 60.

Is #8 rebar 1 inch?

Yes. #8 bar has a nominal diameter of 1.000" and weighs 2.670 lb per foot, with a 0.79 sq in cross-section. Its metric size is 25. Yankocy stocks #3 through #6 in 10' and 20' lengths. Call (203) 261-4955 about larger sizes.

Are rebar chairs necessary?

Bar has to sit at the depth the plans call for, with the required concrete cover. Chairs hold it there while the concrete is placed. Bar laid on the ground ends up at the bottom of the pour. Yankocy stocks 2- and 3-piece rod chairs.

Last updated November 2, 2026

Yankocy sells rebar, rod chairs and caps wholesale to lumber and mason yards. Buying for your own home? Your local lumber or mason yard can order it for you.

Rebar data sheets and sources

• Nucor: rebar sizes and weight per foot
• Gerdau: straight rebar technical specifications
• ASTM A615/A615M: deformed carbon-steel bars for concrete
• CRSI: bar identification and markings
• OSHA 1926.701: concrete and masonry construction requirements

Related to rebar

• Welded wire mesh
• Dura-Wall block mesh
• Sonotube forms
• Lally columns
• All rebar & wire mesh