AWG to mm Converter
Convert American Wire Gauge (AWG) to diameter in mm, cross-section area in mm², and resistance in Ω/km. Includes metric-to-AWG reverse lookup and copper/aluminum current capacity.
Diameter (mm)
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Cross-section Area (mm²) —
Resistance (Ω/km, copper) —
Extended More scenarios, charts & detailed breakdown ▾
Diameter (mm)
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Area (mm²) —
Resistance (Ω/km) —
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Wire Dimensions
Diameter (mm) —
Area (mm²) —
Electrical & Physical
Total Resistance (Ω) —
Approx Current Capacity (A) —
Weight (kg/m) —
How to Use This Calculator
- Enter the AWG gauge number (use negative for large gauges: -3=4/0, -2=3/0, -1=2/0, 0=1/0).
- Diameter, cross-section area, and resistance appear instantly.
- Use Metric to AWG tab to find AWG from an area in mm².
- Use the Reference Table tab for common gauges.
- The Professional tab adds current capacity, weight per meter, and total resistance for a cable run.
Formula
Diameter (in) = 92^((36−AWG)/39)/200 | Area = π(d/2)²
R (Ω/km) = 17.241 / area_mm² (copper)
Example
AWG 10: d = 92^(26/39)/200 ≈ 2.588 mm, Area ≈ 5.26 mm², R ≈ 3.28 Ω/km.
Frequently Asked Questions
- AWG (American Wire Gauge) is a standardized wire gauge system. Lower AWG numbers mean thicker wire. AWG 4/0 is the thickest standard wire; AWG 40 is very fine.
- Diameter (inches) = 92^((36−AWG)/39) / 200. Multiply by 25.4 for mm. AWG 12 ≈ 2.053 mm, AWG 14 ≈ 1.628 mm.
- 2.5 mm² is approximately AWG 13. AWG 12 (3.31 mm²) and AWG 14 (2.08 mm²) are the nearest standard gauges.
- AWG 12 copper wire (3.31 mm²) can carry approximately 20 A at 60°C insulation rating, or 25 A at 75°C. Always check local electrical codes.
- Copper resistivity ≈ 17.241 mΩ·mm²/m (at 20°C). Resistance (Ω/km) = 17.241 / area_mm². AWG 12 has about 5.21 Ω/km.