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WireGaugeCharts

WIRE GAUGE CHARTS

40 wire in mm

Thickness: 0.08 mm diameter (0.003 inches), 0.01 mm² cross-section of solid copper.

40 · 0.08 mm

Specifications

Diameter
0.08 mm
Diameter (imperial)
0.003 in
Cross-section
0.01 mm²
Area (kcmil)
0.0
Copper resistance
1,048.839 Ω/1000 ft
Copper resistance (metric)
3,441.07 Ω/km
Copper weight
0.0 g/m
Free-air rating (typical)
1 A

Nearest metric sizes

0.01 mm² does not match a standard metric cable size exactly. The closest conventional cross-sections are0.5 mm², 0.75 mm² and 1 mm²— engineers round this wire up (larger cross-section) for ampacity, or accept the raw equality for signal work.

One gauge away:39 · thinnerFull chart →

Frequently asked questions

Is 40 gauge wire thick or thin?

40 gauge wire is 0.08 mm in diameter. On the AWG scale a lower number means a thicker wire, so 40 AWG sits near the thin end of the chart.

What diameter is 40 wire in millimeters?

40 gauge wire is 0.08 mm (0.003 in) in diameter, with a solid-conductor cross-section of 0.01 mm².