Wire Size for 20.88 Amps

Typical copper wire gauges for 20.88 amps across common run lengths on a 120V circuit, sized to keep voltage drop under 3% and respect the NEC 240.4(D) small-conductor rule. At 20.88A the load sits in residential-branch territory where aluminum is not a typical conductor, so the table lists copper only. Actual install sizing depends on conductor material, insulation/termination temperature rating, cable type, ambient and bundling derates, and local code.

20.88A Wire Gauge by Distance

DistanceCopper GaugeV-Drop (Cu)NEC Status
25 ft 10 AWG 1.29V (1.08%) check_circle OK
50 ft 10 AWG 2.59V (2.16%) check_circle OK
75 ft 8 AWG 2.44V (2.03%) check_circle OK
100 ft 8 AWG 3.25V (2.71%) check_circle OK
125 ft 6 AWG 2.56V (2.14%) check_circle OK
150 ft 6 AWG 3.08V (2.56%) check_circle OK
175 ft 6 AWG 3.59V (2.99%) check_circle OK
200 ft 4 AWG 2.57V (2.14%) check_circle OK
250 ft 4 AWG 3.22V (2.68%) check_circle OK
300 ft 3 AWG 3.07V (2.56%) check_circle OK
400 ft 2 AWG 3.24V (2.7%) check_circle OK
500 ft 1 AWG 3.22V (2.68%) check_circle OK

Copper gauges use the NEC 240.4(D) branch-circuit cap, not raw 75°C ampacity.

Other Amperages

This calculator provides estimates for reference purposes only. Always consult a licensed electrician and verify compliance with the National Electrical Code (NEC) and local electrical codes before performing any electrical work.