Watts to Amps Converter (12V DC)
Instantly convert Watts to Amps for 12V automotive, solar, and marine systems. Includes wire gauge (AWG) recommendations.
*Wire gauge suggestions assume copper wire, standard insulation, and short cable runs (< 10ft). Consult NEC or a certified electrician for critical systems.
About
DC systems operating at 12 Volts are the standard for automotive electrical systems, marine applications, and off-grid solar setups. Calculating the amperage draw is the first step in installing an amplifier, adding LED light bars, or sizing a solar charge controller. Unlike high-voltage home currents, 12V systems require significantly thicker cables to transmit the same amount of power without dangerous voltage drops.
This tool eliminates the variable of voltage, locking the calculation to 12V DC to provide immediate amperage results. It further assists the installation process by recommending a safe Wire Gauge (AWG) based on standard ampacity tables, helping prevent overheated wires in custom builds.
Formulas
Since the voltage is constant, the formula simplifies to a direct proportion. This applies strictly to Direct Current (DC) systems.
Wire gauge selection roughly follows standard ampacity ratings for short runs (under 10ft/3m). Longer runs require thicker cables to account for resistance.
Reference Data
| Power (W) @ 12V | Current (A) | Min. Wire Gauge (AWG) | Typical Use Case |
|---|---|---|---|
| 10 | 0.83 | 18 AWG | LED Dome Light |
| 60 | 5.0 | 16 AWG | Standard Headlight |
| 120 | 10.0 | 14 AWG | Cigarette Lighter Socket |
| 240 | 20.0 | 12 AWG | High-Power Light Bar |
| 360 | 30.0 | 10 AWG | Small Amplifier |
| 600 | 50.0 | 8 AWG | DC-AC Inverter (Small) |
| 1200 | 100.0 | 4 AWG | Main Battery Winch |
| 2400 | 200.0 | 1/0 AWG | Starter Motor |