ABOUT

Wire Gauge Charts

Most wire-gauge sites either dump a static table on you or trap you in an ad treadmill. We do one thing: compute every number — diameters, areas, resistances, ampacity, voltage drop — locally, from the AWG formula and the NEC ampacity table, so the chart you see is the chart that's true.

The site is built as a static Astro app: no cookies, no trackers, no "accept" banners, and pages render fast on any phone. Everything you enter into the calculator stays in your browser.

How the numbers are computed

Diameters come from the published AWG formula (d = 0.005 × 92^((36−n)/39) inches); areas and resistances derive from that diameter using copper's standard resistivity of 10.371 Ω·cmil/ft at 20 °C. Ampacity figures follow NEC 2023 Table 310.16 for the three insulation columns. Aluminum resistance is copper × 1.64.

Chassis/free-air ratings for sizes below 14 AWG (common in automotive and marine tables) come from industry reference tables; they're marked with a dagger wherever they appear, so you always know which numbers are code-backed and which are shop references.

Editorial standards

• Every chart is generated from one shared math library, so a change updates everywhere.
• Code-backed values cite the source table; reference-only values say so.
• We show the math in our posts, so you can verify any row with a pocket calculator.

Contact

Corrections, missing sizes, or another language: open an issue on the project repository. The site is a work in progress and the gauge math is open for audit.