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Guide Topics
Complete AWG Wire Size Chart & Reference Guide
American Wire Gauge (AWG) comprehensive reference table with diameters, resistance, ampacity ratings, and metric conversions for electrical installations.
Quick AWG Reference - Most Common Sizes
14 AWG
- • Diameter: 1.628 mm
- • 15A circuits
- • Lighting & outlets
12 AWG
- • Diameter: 2.053 mm
- • 20A circuits
- • Kitchen & bathroom
10 AWG
- • Diameter: 2.588 mm
- • 30A circuits
- • Dryers & A/C
6 AWG
- • Diameter: 4.116 mm
- • 60A circuits
- • EV chargers
Complete AWG Wire Size Table
| AWG | Diameter (mm) | Diameter (inch) | Area (mm²) | Resistance (Ω/1000ft) | Cu Ampacity 75°C | Al Ampacity 75°C |
|---|---|---|---|---|---|---|
| 18 | 1.024 | 0.0403 | 0.823 | 6.385 | — | — |
| 16 | 1.291 | 0.0508 | 1.31 | 4.016 | — | — |
| 14 | 1.628 | 0.0641 | 2.08 | 2.525 | 20* | — |
| 12 | 2.053 | 0.0808 | 3.31 | 1.588 | 25* | 20* |
| 10 | 2.588 | 0.1019 | 5.26 | 0.9989 | 35* | 30* |
| 8 | 3.264 | 0.1285 | 8.37 | 0.6282 | 50 | 40 |
| 6 | 4.116 | 0.1620 | 13.30 | 0.3951 | 65 | 50 |
| 4 | 5.189 | 0.2043 | 21.15 | 0.2485 | 85 | 65 |
| 3 | 5.827 | 0.2294 | 26.67 | 0.1970 | 100 | 75 |
| 2 | 6.544 | 0.2576 | 33.62 | 0.1563 | 115 | 90 |
| 1 | 7.348 | 0.2893 | 42.41 | 0.1239 | 130 | 100 |
| 1/0 | 8.252 | 0.3249 | 53.49 | 0.0983 | 150 | 120 |
| 2/0 | 9.266 | 0.3648 | 67.43 | 0.0779 | 175 | 135 |
| 3/0 | 10.40 | 0.4096 | 85.01 | 0.0618 | 200 | 155 |
| 4/0 | 11.68 | 0.4600 | 107.2 | 0.0490 | 230 | 180 |
* Limited by NEC 240.4(D) small conductor rule. 14 AWG max 15A, 12 AWG max 20A, 10 AWG max 30A protection.
AWG to Metric Wire Size Conversion
Common AWG to mm² Conversions
| AWG | mm² | Nearest Metric |
|---|---|---|
| 14 AWG | 2.08 | 2.5 mm² |
| 12 AWG | 3.31 | 4 mm² |
| 10 AWG | 5.26 | 6 mm² |
| 8 AWG | 8.37 | 10 mm² |
| 6 AWG | 13.3 | 16 mm² |
| 4 AWG | 21.2 | 25 mm² |
| 2 AWG | 33.6 | 35 mm² |
| 1/0 AWG | 53.5 | 50 mm² |
AWG System Explained
The AWG system is logarithmic - each 3-gauge decrease doubles the cross-sectional area.
Smaller AWG numbers = larger wire diameters. AWG 0000 (4/0) is the largest standard size.
For sizes larger than 4/0, kcmil (MCM) is used, representing thousands of circular mils.
Formula: Diameter(n) = 0.005 × 92^((36-n)/39) inches
Wire Size Selection by Application
Residential Circuits
- Lighting (15A)14 AWG
- Outlets (20A)12 AWG
- Kitchen GFCI (20A)12 AWG
- Bathroom (20A)12 AWG
Appliances
- Dryer (30A)10 AWG
- Range (50A)6 AWG
- Water Heater (30A)10 AWG
- A/C Unit (20-30A)12-10 AWG
Special Applications
- EV Charger (60A)6 AWG
- Hot Tub (50A)6 AWG
- Sub Panel (100A)2 AWG
- Service (200A)3/0 AWG
Important: These are typical sizes. Always calculate based on actual load, distance, and voltage drop. Consult NEC and local codes for specific requirements.
Wire Cost Comparison by Size
| Wire Size | Copper $/ft | Aluminum $/ft | Savings % | 100ft Cost Cu | 100ft Cost Al |
|---|---|---|---|---|---|
| 14 AWG | $0.45 | — | — | $45 | — |
| 12 AWG | $0.65 | $0.35 | 46% | $65 | $35 |
| 10 AWG | $0.95 | $0.45 | 53% | $95 | $45 |
| 8 AWG | $1.55 | $0.75 | 52% | $155 | $75 |
| 6 AWG | $2.80 | $1.20 | 57% | $280 | $120 |
| 2 AWG | $5.50 | $2.20 | 60% | $550 | $220 |
| 2/0 AWG | $12.50 | $4.80 | 62% | $1,250 | $480 |
*Prices are approximate 2024 market averages for THHN/THWN-2 wire and may vary by location and supplier.
Technical Resources & Standards
NEC Standards
- NFPA 70 - NEC
- • Article 310 - Conductors
- • Table 310.16 - Ampacities
- • Chapter 9, Table 8 - Properties
Industry Standards
- ASTM B258 - AWG Sizes
- UL Wire & Cable Guide
- • IEC 60228 - Metric sizes
Manufacturer Data
- Southwire Specifications
- General Cable Resources
- • Wire specification sheets