Cable AWG Converter
Convert between AWG wire gauge numbers, cross-sectional area in mm², diameter in inches and mm, and maximum ampacity ratings.
Select an AWG size or enter a cross-sectional area — all other values calculate automatically.
12 AWG (3.31 mm²) = 20 A circuits
10 AWG (5.26 mm²) = 30 A circuits
Understanding AWG (American Wire Gauge)
The American Wire Gauge system is the standard method for measuring wire and cable sizes in North America. The AWG number is inversely related to the wire diameter: smaller AWG numbers indicate thicker wires. This counterintuitive numbering system dates back to the number of drawing passes needed to produce the wire — more passes meant thinner wire and a higher gauge number.
AWG Conversion Formulas:
The diameter of an AWG wire can be calculated mathematically:
Diameter (inches) = 0.005 × 92^((36 - AWG) / 39)
Diameter (mm) = Diameter (inches) × 25.4
Cross-sectional area (mm²) = π/4 × Diameter(mm)²
These formulas produce exact values for any AWG number, including fractional sizes.
Common AWG Wire Sizes Reference Table:
| AWG | Diameter (mm) | Area (mm²) | Ampacity (copper, 60°C) |
|---|---|---|---|
| 0000 (4/0) | 11.68 | 107.2 | 230 A |
| 000 (3/0) | 10.40 | 85.0 | 200 A |
| 00 (2/0) | 9.27 | 67.4 | 175 A |
| 0 (1/0) | 8.25 | 53.5 | 150 A |
| 2 | 6.54 | 33.6 | 115 A |
| 4 | 5.19 | 21.2 | 85 A |
| 6 | 4.11 | 13.3 | 65 A |
| 8 | 3.26 | 8.37 | 40 A |
| 10 | 2.59 | 5.26 | 30 A |
| 12 | 2.05 | 3.31 | 20 A |
| 14 | 1.63 | 2.08 | 15 A |
| 16 | 1.29 | 1.31 | — |
| 18 | 1.02 | 0.82 | — |
| 20 | 0.81 | 0.52 | — |
| 22 | 0.64 | 0.33 | — |
| 24 | 0.51 | 0.20 | — |
Practical Examples:
- Standard US household wiring uses 14 AWG (2.08 mm²) for 15-amp circuits and 12 AWG (3.31 mm²) for 20-amp circuits.
- A 30-amp dryer circuit requires 10 AWG (5.26 mm²) copper wire.
- An electric stove on a 50-amp circuit needs 6 AWG (13.3 mm²) copper wire.
- Speaker wire for home audio is typically 16 AWG (1.31 mm²) for short runs and 12 AWG (3.31 mm²) for long runs.
AWG to Metric (IEC) Comparison: The metric system uses cross-sectional area in mm² directly, while AWG uses gauge numbers. Common equivalents: 14 AWG is close to 2.5 mm², 12 AWG is close to 4 mm², 10 AWG is close to 6 mm².
Tips:
- Every decrease of 3 AWG numbers roughly doubles the cross-sectional area (and ampacity).
- Every decrease of 6 AWG numbers roughly doubles the diameter.
- Aluminum wire requires a larger gauge than copper for the same ampacity (typically 2 sizes larger).
- Ampacity ratings depend on insulation type, ambient temperature, and installation method. Always consult the National Electrical Code (NEC) for specific applications.