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Wire Gauge Size Chart

Type an AWG gauge number, choose a wire material, and press Calculate to see the diameter, cross sectional area and resistance for that size. Both 0000 and 4/0 return the same figures.

About this wire gauge size chart

The form has two fields and one button. Enter the size in the Gauge # (AWG) box as a plain number such as 12 or 36, or in the /0 form such as 2/0 or 4/0, then choose Copper or Aluminum in the Wire material list and press Calculate.

The answers appear in cards below the button: diameter in inches and millimeters, cross sectional area in kcmil, square inches and square millimeters, and resistance per 1000 feet and per 1000 meters. Wire material sets the conductor for the resistance cards. Copy puts a result together with its unit onto your clipboard, and Clear resets the form.

Entering 12 with Copper gives Diameter (inches): 0.080808086161179 in; Diameter (millimeters): 2.05252538849395 mm; Cross sectional area (kcmil): 6.52994678903254 kcmil; Cross sectional area (square inches): 0.00512860821518922 in². Entering 36 gives Diameter (inches): 0.005 in; Diameter (millimeters): 0.127 mm; Cross sectional area (kcmil): 0.025 kcmil; Cross sectional area (square inches): 0.0000196349540849362 in².

AWG wire diameter formula

Every size on this chart comes from one expression, written with the gauge number in place of n: d = 0.005 in × 92^((36 − n) / 39). The answer is a diameter in inches, and it heads the result cards, alongside millimeters, cross sectional area and resistance.

Gauge 36 gives d = 0.005 in × 92^((36 − 36) / 39) = 0.005 in. Gauge 12 gives d = 0.005 in × 92^((36 − 12) / 39) ≈ 0.080808086161179 in. Gauge 2/0 gives d = 0.005 in × 92^((36 − -1) / 39) ≈ 0.364796584608142 in.

The two spellings 0000 and 4/0 behave the same way: both give d = 0.005 in × 92^((36 − -3) / 39) = 0.46 in, with a diameter of 11.684 mm and a cross sectional area of 211.6 kcmil or 0.1661902513749 in².