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WireGaugeCharts

WIRE GAUGE CHARTS

1/0 wire in mm

Thickness: 8.25 mm diameter (0.325 inches), 53.48 mm² cross-section of solid copper.

1/0 · 8.25 mm

Specifications

Diameter
8.25 mm
Diameter (imperial)
0.325 in
Cross-section
53.48 mm²
Area (kcmil)
105.5
Copper resistance
0.098 Ω/1000 ft
Copper resistance (metric)
0.32 Ω/km
Copper weight
479.1 g/m
Ampacity (NEC 75 °C)
150 A

Nearest metric sizes

53.48 mm² does not match a standard metric cable size exactly. The closest conventional cross-sections are35 mm², 50 mm² and 70 mm²— engineers round this wire up (larger cross-section) for ampacity, or accept the raw equality for signal work.

One gauge away:1 · thinner2/0 · thickerFull chart →

Frequently asked questions

Is 1/0 gauge wire thick or thin?

1/0 gauge wire is 8.25 mm in diameter. On the AWG scale a lower number means a thicker wire, so 1/0 AWG sits toward the thick end, where service and feeder wires live.

How many amps can 1/0 gauge wire carry?

NEC Table 310.16 rates 1/0 AWG copper at 150 A in the 75 °C column (see our amp chart for 60/75/90 °C ratings). Use the calculator to check voltage drop at your run length; long runs often force one size thicker.

What diameter is 1/0 wire in millimeters?

1/0 gauge wire is 8.25 mm (0.325 in) in diameter, with a solid-conductor cross-section of 53.48 mm².