Voltage Drop Calculator
Calculate electrical voltage drop and wire sizing per NEC 210.19. Maximum 3% for branch circuits, 5% for feeders.
Quick Presets
Circuit Parameters
Wire Specifications
Voltage Drop Calculation
2.57%
NEC Compliant
Voltage Drop
3.09V
Final Voltage
116.91V
Wire Resistance
1.9300 Ω/1000ft
Temp Correction
1.00
Wire Size Comparison
14 AWG
4.91V drop
4.09%
⚠ OK
12 AWG
3.09V drop
2.57%
✓ Good
10 AWG
1.94V drop
1.61%
✓ Good
8 AWG
1.22V drop
1.02%
✓ Good
6 AWG
0.79V drop
0.65%
✓ Good
4 AWG
0.49V drop
0.41%
✓ Good
3 AWG
0.39V drop
0.33%
✓ Good
2 AWG
0.31V drop
0.26%
✓ Good
NEC Guidelines
NEC 210.19(A): Branch circuit voltage drop
• Branch circuits: 3% maximum voltage drop
• Feeders: 5% maximum voltage drop
• Total branch circuit + feeder: 5% maximum
• Measured at farthest outlet when circuit is fully loaded
⚠️ This calculator is for reference only. Always verify with local AHJ and current NEC requirements.