Circuit Breaker Sizes & Amperage

Direct Answer

Residential and commercial circuit breakers are standardized under National Electrical Code (NEC Article 240) and UL 489 into standard continuous trip ratings (15A, 20A, 30A, 40A, 50A, 60A, 100A, 200A), single-pole (120V) vs double-pole (240V) formats, and mandatory AFCI/GFCI protection types.

Source: NFPA 70: National Electrical Code (NEC) Article 240 / UL 489 Molded-Case Circuit Breakers · Last reviewed Aug 28, 2026

Specs

Governing Standards	NFPA 70 (NEC) / UL 489 / NEMA AB 1 (Circuit Breakers)
15-Amp Single Pole (120V)	Wire Gauge: 14 AWG Copper \| Standard residential lighting and general bedroom/living outlets
20-Amp Single Pole (120V)	Wire Gauge: 12 AWG Copper \| Kitchen countertop, bathroom receptacles, laundry, garage, workshop
30-Amp Double Pole (240V)	Wire Gauge: 10 AWG Copper \| Electric clothes dryers, 30-gallon water heaters, small RV hookups
40-Amp Double Pole (240V)	Wire Gauge: 8 AWG Copper \| Electric cooking ranges, cooktops, heat pump auxiliary heat
50-Amp Double Pole (240V)	Wire Gauge: 6 AWG Copper \| Level 2 EV charging (NEMA 14-50), commercial cooking ovens
60-Amp Double Pole (240V)	Wire Gauge: 4 AWG Copper (or 6 AWG THHN) \| Central air conditioning compressors, sub-panel feeds
100A–200A Main Service	2/0 AWG Copper / 4/0 AWG Aluminum \| Main residential service disconnect panel
80% Continuous Load Rule	NEC 210.20: Continuous loads (operating 3+ hours) must not exceed 80% of breaker rating (e.g. 16A max on 20A breaker)

Standard Circuit Breaker Amperage, Voltage & Wire Gauge Pairing Matrix

Breaker Amperage Rating	Standard Operating Voltage	Breaker Pole Type	Minimum Copper Wire Gauge (AWG)	Maximum Continuous Load (80% Rule)	Typical Residential Household Application
15 Amps	120V AC	Single Pole (1-Pole)	14 AWG Copper	12 Amps (1,440 Watts)	General lighting, bedroom & living room receptacles
20 Amps	120V AC	Single Pole (1-Pole)	12 AWG Copper	16 Amps (1,920 Watts)	Kitchen small appliances, Bathroom GFCIs, Garage
30 Amps	240V AC	Double Pole (2-Pole)	10 AWG Copper	24 Amps (5,760 Watts)	Electric Clothes Dryer, 240V Water Heater, 30A RV
40 Amps	240V AC	Double Pole (2-Pole)	8 AWG Copper	32 Amps (7,680 Watts)	Electric kitchen range, induction cooktop, large AC
50 Amps	240V AC	Double Pole (2-Pole)	6 AWG Copper	40 Amps (9,600 Watts)	Level 2 EV Fast Charger (40A continuous), Sub-panel
60 Amps	240V AC	Double Pole (2-Pole)	4 AWG Copper	48 Amps (11,520 Watts)	48A Hardwired EV Charger, Whole-house heat pump
100 Amps	240V AC	Double Pole	1 AWG Cu / 1/0 Al	80 Amps	Detached garage sub-panel, small home main service
200 Amps	240V AC	Double Pole (Main)	2/0 Cu / 4/0 Al	160 Amps	Standard Modern Single-Family Home Main Service

Standard vs GFCI vs AFCI vs Dual-Function (DFCI) Breakers

Standard Thermal-Magnetic: Protects strictly against wire overheating (overcurrent) and direct dead shorts.
GFCI (Ground Fault Circuit Interrupter): Detects 4–6 mA current leakages to ground within 25 milliseconds to prevent fatal human electrocution (mandatory near sinks, outdoors, bathrooms, garages).
AFCI (Arc Fault Circuit Interrupter): Uses onboard digital microprocessors to detect hazardous electrical arcing signatures caused by damaged wires or loose screw terminals that cause house fires (mandatory in bedrooms, living rooms, and hallways under modern NEC).
Dual-Function (DFCI / CAFCI): Combines both AFCI fire prevention and GFCI shock protection in a single breaker body.