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AWG to mm / mm2 Converter

Pick a direction in the Conversion mode box, type your value, and press Calculate to see the gauge, the diameter and the cross-sectional area together.

What this tool does

AWG means American wire gauge, the numbering used for wire sizes. The Conversion mode box offers three directions: AWG gauge to diameter & area, Diameter to AWG, and Cross-sectional area to AWG. Each direction has its own field — Wire gauge, Diameter or Cross-sectional area — and nothing is worked out until you press Calculate.

The answers then appear in cards below the button: the wire gauge, the diameter in millimeters and inches, and the cross-sectional area in square millimeters and square inches. For Wire gauge: 12 the cards read Wire gauge: 12 AWG; Diameter: 2.0525 mm; Diameter: 0.0808 in; Cross-sectional area: 3.3088 mm²; Cross-sectional area: 0.0051 in². Use Copy to write a result and its unit to the clipboard, and Clear to reset the form.

The AWG to mm formula

The gauge number and the size run in opposite directions, so a larger AWG number is a thinner wire: moving from 12 AWG to 14 AWG takes the diameter from 2.0525 mm down to 1.6277 mm and the area from 3.3088 mm² down to 2.0809 mm². The area is measured straight across the wire, so it follows the diameter and shrinks faster than it does — for a diameter of 2.0525 mm the cross-sectional area is ≈ 3.3088 mm².

Very thick wire sizes use zero notation: Wire gauge: 0000 gives Diameter: 11.684 mm (0.46 in) and Cross-sectional area: 107.2193 mm² (0.1662 in²), while Wire gauge: 00 gives Diameter: 9.2658 mm (0.3648 in) and Cross-sectional area: 67.4309 mm² (0.1045 in²). Going the other way, a diameter or an area is matched to an AWG size, so Conversion mode: Diameter to AWG with Diameter: 2.0525 and Conversion mode: Cross-sectional area to AWG with Cross-sectional area: 3.3088 both return Wire gauge: 12 AWG.