Shop electrical calculator
Enter the total nameplate wattage of the tools on a circuit, pick voltage, and toggle continuous duty (for dust collectors and air compressors that run > 3 hours). Recommended breaker size and wire gauge follow common NEC residential branch-circuit limits.
Amps drawn: 12.75 A
Recommended breaker: 15 A · wire gauge: 14 AWG copper
This is a planning tool, not professional advice. Electrical work on your home should be inspected — and in many jurisdictions performed — by a licensed electrician.
The math
amps = (watts × power-factor) / volts. For continuous loads the NEC requires a breaker rated ≥ load / 0.8, so we divide by 0.8 when continuous duty is on. Power factor defaults to 0.85 (typical induction motor); resistive loads (heaters) use 1.0.