Rebar Size Converter

Compare US rebar sizes, metric rebar sizes, bar diameter, cross-sectional area, weight per foot, weight per meter, inches, millimeters, square inches, and square millimeters.

Convert Rebar Size

#4 rebar = 0.500 in diameter
Your rebar size result will appear here.

Common rebar size references

#3 rebar:
0.375 in diameter / 0.11 in² area / 0.376 lb/ft

#4 rebar:
0.500 in diameter / 0.20 in² area / 0.668 lb/ft

#5 rebar:
0.625 in diameter / 0.31 in² area / 1.043 lb/ft

#6 rebar:
0.750 in diameter / 0.44 in² area / 1.502 lb/ft

Where rebar size conversions are used

Rebar size conversions are useful for concrete slabs, footings, foundations, retaining walls, columns, beams, driveways, patios, masonry reinforcement, structural drawings, and material takeoffs.

Use this converter when comparing US bar sizes, metric rebar sizes, diameter, area, unit weight, and total bar weight.

What your rebar size result means

Your result shows the selected rebar size converted into diameter, cross-sectional area, weight per foot, weight per meter, and estimated total weight for the length and bar count entered.

Rebar sizing for structural concrete depends on engineering design, spacing, cover, grade, lap length, concrete strength, building code, and project specifications. This converter is for size comparison and estimating only.

Rebar size converter tips

Frequently asked questions

What size is #4 rebar?

#4 rebar is 0.500 inches in diameter, or about 12.7 millimeters.

What size is #5 rebar?

#5 rebar is 0.625 inches in diameter, or about 15.875 millimeters.

How are US rebar sizes named?

US rebar sizes are based on eighths of an inch. For example, #6 rebar is 6 eighths of an inch, or 3/4 inch diameter.

How much does #4 rebar weigh?

#4 rebar weighs about 0.668 pounds per foot, or about 0.994 kilograms per meter.

Does this converter choose the correct rebar size?

No. This converter compares rebar dimensions and weights. Correct rebar size depends on structural design, loads, code, spacing, and engineering requirements.