American Wire Gauge (AWG) is a standardized, logarithmic wire sizing system where each step is defined by a precise mathematical relationship rather than a round metric number. The formula d(mm) = 0.127×92(36−AWG)/39 is built so that AWG 36 has a diameter of exactly 0.127 mm (5 mils), and every 3 gauge sizes doubles the cross-sectional area (and therefore roughly doubles the current-carrying capacity, all else equal) — a deliberately engineered logarithmic progression, not an arbitrary historical accident.
| AWG | Diameter (mm) | Area (mm²) |
|---|---|---|
| 10 | 2.588 | 5.261 |
| 12 | 2.053 | 3.309 |
| 14 | 1.628 | 2.081 |
| 16 | 1.291 | 1.309 |
| 18 | 1.024 | 0.823 |
| 20 | 0.812 | 0.518 |
| 22 | 0.644 | 0.326 |
| 24 | 0.511 | 0.205 |
Once you have your wire's diameter or area, cross-reference with the Trace Width or Voltage Drop calculators to check current-carrying capacity or resistance for a specific length.
Use d(mm)=0.127×92^((36-AWG)/39) to find the diameter, then Area=π/4×d² for the cross-sectional area — or use the calculator above to get both instantly from just the AWG number.
This is simply how the American Wire Gauge scale was historically defined — it counts down from thin to thick, likely originating from the number of drawing operations needed to produce that wire size (more drawing passes through progressively smaller dies made thinner wire, with a higher gauge number).
Approximately AWG 13, between the standard AWG 12 (3.31 mm²) and AWG 14 (2.08 mm²) sizes — there is no exact AWG equivalent since the two systems are on fundamentally different numbering schemes.
Yes, by design — stepping 3 gauge numbers changes the diameter by a factor of 92^(3/39)≈1.416, and since area scales with diameter squared, 1.416²≈2.005 — almost exactly double. This is a deliberate feature of the AWG formula's exponent, not a coincidence.
AWG 14 is common for 15-amp circuits, and AWG 12 for 20-amp circuits, in typical US residential wiring — always follow local electrical code requirements rather than sizing purely by calculation for actual installations.
AWG 22 is a very common choice for solderless breadboard jumper wires and general low-current hookup wire in hobby electronics.
No — it calculates only the bare conductor diameter/area. Insulated wire's overall (jacketed) diameter is larger and depends on the specific insulation material and thickness, which varies by manufacturer and wire type.
Once you have the cross-sectional area, use the Trace Width or Wire Gauge/Ampacity calculators (using the appropriate current-density or IPC-2221-style formula) — this AWG converter only handles the geometric size conversion, not current capacity.
Stranded wire of the same AWG rating has the same total conductor cross-sectional area as solid wire, but its overall outer diameter is typically slightly larger due to the gaps between individual strands.
Minor differences can arise from rounding conventions or from tables listing nominal/rounded industry-standard values rather than the exact mathematical formula result — the values here are computed directly from the precise AWG formula for maximum accuracy.
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