mm² to AWG Converter
Convert square millimeters to American Wire Gauge with precision matching, comprehensive specifications, and professional electrical engineering data
Formula: Convert area to diameter, then AWG = -39 × log₁₀(diameter) + 36
This calculator converts wire cross-sectional area in square millimeters to the equivalent American Wire Gauge (AWG) size.
Complete mm² to AWG Reference Chart
Detailed conversion table with wire specifications, applications, and electrical characteristics for professional use
| Area (mm²) | AWG Size | Diameter (mm) | Resistance (Ω/km) | Ampacity (A) | Typical Applications |
|---|---|---|---|---|---|
| 0.051 | 30 | 0.255 | 103.2 | 0.5 | Magnet wire, fine electronics, precision instruments |
| 0.081 | 28 | 0.321 | 64.9 | 0.8 | Thermocouple wire, instrumentation, sensor cables |
| 0.129 | 26 | 0.405 | 40.8 | 1 | Computer cables, telephone wire, data transmission |
| 0.205 | 24 | 0.511 | 25.7 | 1.5 | Signal cables, low power electronics, control circuits |
| 0.326 | 22 | 0.644 | 16.1 | 2.5 | Control circuits, alarm systems, communication |
| 0.518 | 20 | 0.812 | 10.2 | 4 | Lighting circuits, control panels, low voltage |
| 0.823 | 18 | 1.024 | 6.39 | 7 | Appliance cords, fixture wiring, extension cords |
| 1.31 | 16 | 1.291 | 4.02 | 10 | Extension cords, outlet circuits, small appliances |
| 2.08 | 14 | 1.628 | 2.53 | 15 | Branch circuits, outlets, lighting, general wiring |
| 3.31 | 12 | 2.053 | 1.59 | 20 | Kitchen circuits, bathroom outlets, air conditioning |
| 5.26 | 10 | 2.588 | 1 | 30 | Electric dryers, ranges, large appliances |
| 8.37 | 8 | 3.264 | 0.628 | 40 | Sub-panels, large appliances, electric water heaters |
| 13.3 | 6 | 4.115 | 0.395 | 55 | Service entrance, feeders, sub-panel connections |
| 21.2 | 4 | 5.189 | 0.248 | 70 | Service entrance, sub-panels, large load feeders |
| 26.7 | 3 | 5.827 | 0.197 | 85 | Service entrance, industrial feeders, large motors |
| 33.6 | 2 | 6.544 | 0.156 | 95 | Service entrance, large industrial loads, feeders |
| 42.4 | 1 | 7.348 | 0.124 | 110 | Service entrance, industrial applications, large feeders |
| 53.5 | 1/0 | 8.252 | 0.098 | 125 | Service entrance, industrial feeders, large installations |
| 67.4 | 2/0 | 9.266 | 0.078 | 145 | Service entrance, industrial applications, main feeders |
| 85 | 3/0 | 10.405 | 0.062 | 165 | Service entrance, industrial feeders, large facilities |
| 107.2 | 4/0 | 11.684 | 0.049 | 195 | Service entrance, industrial feeders, major installations |
From Metric to Standard: The Conversion Process
Converting a wire's cross-sectional area from square millimeters (mm²) to AWG is a two-step process that bridges the metric area measurement with the imperial gauge system.
Step 1: Area to Diameter
First, the cross-sectional area (A) must be converted into an effective diameter (d). The formula for the diameter of a circle derived from its area is:
d = 2 * √(A / π)
Step 2: Diameter to AWG
Once the diameter is found in millimeters, it can be plugged into the standard formula to find the AWG number (n):
n = -39 * log₁₀(d / 0.127) + 36
Why This Matters
This conversion is essential when working with international components specified in mm² for use in systems designed around North American AWG standards. Always select the next lowest AWG number (thicker wire) if your calculation falls between standard sizes to ensure safety and performance.
Conversion Method
Algorithm: Closest match selection
Tolerance: ±5% typical variance
Standard: ASTM B258-02
Reference: 20°C copper
Precision: 0.01 mm² resolution
Wire Construction
Solid: AWG 30-10 typical
Stranded: AWG 18 and larger
Class B: Standard stranding
Class C: Flexible stranding
Material: Annealed copper
Global Standards
Wire Size Selection Guide
Professional guidelines for selecting appropriate wire sizes based on application requirements
High Power
4/0 - 1/0 AWG
53-107 mm²
Service entrance
Industrial feeders
125-230A capacity
Medium Power
2 - 8 AWG
8.4-33.6 mm²
Sub-panels
Large appliances
40-95A capacity
Branch Circuits
10 - 14 AWG
2.1-5.3 mm²
Outlets & lighting
Kitchen circuits
15-30A capacity
Control & Signal
16 - 30 AWG
0.05-1.3 mm²
Instrumentation
Communication
Low voltage
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