Wire Gauge Calculator
Calculate the recommended wire gauge (AWG) for your electrical project. Input current, distance, and voltage to find the right wire size and voltage drop.
AWG Reference Table (Copper)
| AWG | Ampacity (60C) | Ampacity (75C) | Common Use |
|---|---|---|---|
| 14 | 15A | 20A | Lighting circuits |
| 12 | 20A | 25A | General outlets |
| 10 | 30A | 35A | Dryers, AC units |
| 8 | 40A | 50A | Ranges, large appliances |
| 6 | 55A | 65A | Large AC, sub-panels |
| 4 | 70A | 85A | Feeders |
| 2 | 95A | 115A | Service entrance |
| 1/0 | 125A | 150A | Service entrance |
How to Use the Wire Gauge Calculator
- Enter the current draw in amps for your circuit.
- Enter the one-way distance from the panel to the load in feet.
- Enter the system voltage (120V, 240V, etc.).
- Select single-phase or three-phase.
- Set maximum acceptable voltage drop (3% is standard).
- Click Calculate to see the recommended wire gauge.
Why Voltage Drop Matters
Excessive voltage drop in wiring can cause equipment malfunction, reduced efficiency, and safety hazards. The NEC recommends a maximum voltage drop of 3% for branch circuits and 5% for combined feeder and branch circuits. Longer runs and higher currents require larger wire gauges.
Features
- Voltage drop calculation for copper conductors
- Single-phase and three-phase support
- Configurable maximum voltage drop percentage
- Complete AWG reference table with ampacities
- One-click copy result to clipboard
- 100% client-side processing for full privacy
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