Electrical Wire Gauge & Voltage Drop Calculator

Calculate the correct wire gauge per NEC (National Electrical Code) requirements. Accounts for voltage drop, ampacity, and conductor material.

Voltage (V)

Load Current (Amps)

One-Way Distance (ft)

Phase

Conductor Material

Max Voltage Drop (%)

8 AWG

Recommended Wire Gauge

2.09%

Voltage Drop

2.51V

Voltage Lost

40A

Wire Ampacity

Technical Details

Power Loss

50.2 Watts

Conductor

copper

NEC Reference

NEC 210.3

Round Trip Distance

200 ft

⚠️ Safety Warning: Incorrect wire sizing can cause fires. Always verify calculations with a licensed electrician. Wire must be sized for both ampacity AND voltage drop. All electrical work should comply with NEC and local codes.