Wire Calculator

Calculate the right wire gauge for your amplifier based on current draw, cable length, and acceptable voltage drop. Undersized wires cause power loss, voltage sag, and can be a fire hazard.

System Parameters

Wire Type

Oxygen-Free Copper - Best conductivity, more expensive

System Voltage (V)

Typical: 12.6V (engine off), 13.8-14.4V (engine running)

Current Draw (Amps)

Cable Length (feet, one-way)

Battery to amp (not round-trip - calculator handles that)

Number of Wire Runs

Multiple parallel runs share current, allowing smaller gauge per run

Max Acceptable Voltage Drop (V)

Recommended Wire

2 AWG

Oxygen-Free Copper

Performance Analysis

Actual Voltage Drop0.469V (3.4%)

Power Loss in Wire46.9W

Voltage at Amp13.33V

Wire Capacity Used94%

Wiring Best Practices

•Ground wire should be the same gauge as your power wire—current flows both ways
•Install your main fuse within 18 inches of the battery terminal connection
•Sand or grind the chassis at ground points—paint and primer add resistance
•High-power builds benefit from upgrading the alternator charge wire and grounds (Big 3)
•Oxygen-free copper (OFC) conducts better and resists corrosion compared to CCA

AWG Quick Reference

Gauge	OFC Max Amps*	CCA Max Amps*	Typical Use
4/0 (0000)	400A	250A	Extreme competition
3/0 (000)	350A	220A	High-power competition
2/0 (00)	300A	190A	Multiple high-power amps
1/0 (0)	250A	160A	2000-4000W systems
1 AWG	200A	125A	1500-2500W systems
2 AWG	175A	110A	1000-2000W systems
4 AWG	125A	80A	500-1000W systems
8 AWG	65A	40A	200-500W systems

*Approximate values for 15 ft runs with 3% voltage drop. Actual requirements vary by length and acceptable voltage drop.