Wire Gauge (AWG) Calculator
Enter an American Wire Gauge (AWG) number to see the wire's diameter, cross-sectional area, and typical current capacity.
How AWG wire sizing works
American Wire Gauge (AWG) is a standardized sizing system where a lower number means a thicker wire. The diameter follows a geometric formula: each decrease of 3 gauge numbers roughly doubles the wire's cross-sectional area, and each decrease of 6 numbers roughly doubles its diameter.
Ampacity — the maximum current a wire can safely carry — depends on diameter, insulation type, and installation conditions. The values shown here are typical free-air estimates for copper wire and should not replace your local electrical code for actual wiring projects.
Frequently asked questions
Why does a smaller AWG number mean a thicker wire?
AWG sizing originated from the number of drawing passes needed to produce the wire — more passes (a higher number) through progressively smaller dies produces a thinner wire.
Is the ampacity value exact?
No — ampacity depends on insulation material, ambient temperature, bundling, and installation method. The figures here are general free-air estimates; always check your local electrical code for actual wiring work.
What's the difference between solid and stranded wire of the same gauge?
A solid and stranded wire of the same AWG number have approximately the same total cross-sectional area, but stranded wire has a slightly larger outer diameter due to the gaps between individual strands.