Watt and Ampere Calculator
Solar System Tool

Solar Watts to Amps Calculator

Convert solar panel wattage to current in amps. Critical for sizing charge controllers, battery cables, and combiner boxes. Most solar systems are DC: use voltage 12V, 24V, or 48V depending on your bank.

Conversion direction
Electrical system
Quick voltage presets
Calculated result1000 W · 120 V · DC
8.333 A
Formula usedI = P / V

Custom voltage is always supported.

Formulas Used

DCI = P / V

No power factor needed for DC circuits.

AC 1φI = P / (V × PF)

Single-phase AC — multiply voltage by power factor.

AC 3φI = P / (√3 × V × PF)

Three-phase AC — divide by √3 ≈ 1.732.

Frequently Asked Questions

How many amps does a 400W solar panel produce at 24V?

400 / 24 = 16.67 A. This is the maximum charge current. Size your charge controller at least 25% higher: 16.67 x 1.25 = 20.8 A minimum.

Should I use peak watts or rated watts?

Use the panel's rated (STC) watts for calculations. Real-world output is typically 75-80% due to temperature, shading, and irradiance. Always oversize charge controllers by 25%.