Quick Reference — 10 AWG
Common uses: Dryer circuits, 30A appliances, water heaters, workshop circuits
Wire Properties
| AWG Size | 10 AWG |
| Diameter (inches) | 0.1019″ |
| Diameter (mm) | 2.588 mm |
| Cross-sectional area | 5.26 mm² (10380 circular mils) |
| Resistance — Copper | 0.999 Ω per 1000 ft @ 20°C |
| Resistance — Aluminum | 1.64 Ω per 1000 ft @ 20°C |
| Weight (copper) | ~31.4 lb per 1000 ft |
Ampacity (Current Carrying Capacity)
Per NEC Table 310.16 — Copper conductor, 3+ current-carrying conductors in raceway/cable:
| Insulation Rating | Ampacity |
|---|---|
| 60°C (TW, UF) | 30A |
| 75°C (THW, THWN, XHHW) | 35A |
| 90°C (THHN, XHHW-2) | 40A |
Note: Actual ampacity may be reduced by ambient temperature corrections and conduit fill derating factors per NEC 310.15.
Voltage Drop Example
For a 15A load on 10 AWG copper wire, 100 ft one-way run (120V circuit):
Wire resistance: 0.999 Ω/1000ft × 200ft (round trip) ÷ 1000 = 0.1998 Ω
Voltage drop: 15A × 0.1998 Ω = 3.00V
Percent drop: 3.00V ÷ 120V = 2.5%
NEC recommends ≤3% voltage drop for branch circuits, ≤5% total (feeder + branch).
Nearby Sizes for Comparison
| AWG | Dia (in) | Dia (mm) | Area (mm²) | Ω/1000ft Cu | Ampacity 75°C |
|---|---|---|---|---|---|
| 8 | 0.1285 | 3.264 | 8.37 | 0.628 | 50A |
| 10 | 0.1019 | 2.588 | 5.26 | 0.999 | 35A |
| 12 | 0.0808 | 2.053 | 3.31 | 1.588 | 25A |
⚠️ AWG Sizing Reminder
- In AWG, lower numbers = thicker wire. 4 AWG is much thicker than 14 AWG.
- Each 3-gauge decrease doubles the cross-sectional area (e.g., 11 AWG ≈ 2× the area of 14 AWG).
- Each 6-gauge decrease doubles the diameter.
- Always follow local electrical codes — NEC values are minimum requirements.
Calculate voltage drop for your circuit
Stop looking it up twice — run the numbers and keep the record.
This reference is free forever. When you need to actually calculate, document, and defend the result, do it in the app — then export a clean report you can hand to a reviewer.
- ✓46 engineering calculators, unlimited
- ✓Save & reload every calculation
- ✓Organize work into project folders
- ✓Branded, PE-stamped PDF reports
Free plan, no credit card. Upgrade only when it's paying for itself.