Every circuit breaker in a standard panel is rated at one of a fixed list of amperages defined by NEC Table 240.6(A) — you can't buy a "27 Amp" breaker. This chart lines up the most common breaker sizes with the copper wire gauge they require and the household circuits each size typically protects.
Use it as a quick sanity check when you're looking at a panel schedule or planning a new circuit — then confirm your exact load with the calculator below before you buy wire or a breaker.
Standard Breaker Amp Chart
| Standard Breaker Size (Amps) | Wire Gauge (Copper) | Common Use |
|---|---|---|
| 15A | 14 AWG | General lighting & standard receptacles |
| 20A | 12 AWG | Kitchen counter, bathroom & laundry receptacles |
| 30A | 10 AWG | Clothes dryer, electric water heater |
| 40A | 8 AWG | Electric range / stove (lower-draw models) |
| 50A | 6 AWG | Electric range (higher-draw models), NEMA 14-50 EV/RV outlet, hot tub* |
| 60A | 6 AWG | Large EV wall connector (48A), small sub-panel feeder |
*Hot tub circuits vary by model — always size from the equipment's nameplate and installation manual rather than this chart alone. Wire sizes above assume standard 75°C copper THHN/THWN-2 conductors per NEC Table 310.16; always verify against your equipment nameplate and local code.
Verify Your Exact Circuit
Enter your specific load type and current draw for a precise breaker and wire size result.
Every Standard Breaker Size (NEC 240.6(A))
The chart above covers common household circuits, but NEC Table 240.6(A) defines every standard rating a breaker or fuse can legally be manufactured at, from small branch circuits up through industrial mains:
| Category | Standard Ratings (Amps) |
|---|---|
| Small Branch | 15, 20, 25, 30, 35, 40, 45, 50 |
| Medium Distribution | 60, 70, 80, 90, 100, 110, 125, 150 |
| Large Feeders | 175, 200, 225, 250, 300, 350, 400, 450, 500, 600 |
Feeders and services above 600A continue in standard steps up to 6000A, but those fall outside typical residential and light-commercial work covered by this chart.
Why Some Circuits Jump Straight to 30A or 50A
Notice there's no 25A or 35A row above, even though those are valid standard sizes under NEC Table 240.6(A). That's because most household appliance circuits are dedicated, single-purpose circuits sized directly from the appliance's nameplate wattage — a water heater or dryer lands almost exactly on 30A once you apply the continuous-load math, so that's the size you'll see in the overwhelming majority of homes.
Key Rules Behind This Chart
- Wire gauge sets the ceiling, not the breaker: Per NEC 240.4(D), 14 AWG copper is capped at 15A and 12 AWG at 20A no matter what the connected load calculates to.
- 240V appliance circuits use double-pole breakers: Dryers, water heaters, and ranges are wired at 240V, so their "30A" or "50A" breaker is a double-pole unit occupying two slots in the panel.
- Standard sizes only: All breaker ratings come from NEC Table 240.6(A) — a calculated load of 23.4A always rounds up to the next standard size (30A), never down.
Frequently Asked Questions
What are the standard breaker amp sizes?
Per NEC Table 240.6(A), standard breaker ratings include 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 125, and 150 Amps for typical residential and light commercial branch circuits, with larger standard ratings continuing up to 6000 Amps for industrial services.
What size wire goes with a 20 amp breaker?
A 20 Amp breaker requires a minimum of 12 AWG copper wire. This is the standard for kitchen counter, bathroom, and laundry receptacle circuits under NEC 210.11(C).
Why do some circuits use 15A and others 20A for similar outlets?
General lighting and standard receptacle circuits are commonly 15A on 14 AWG wire, while kitchen, bathroom, and laundry receptacle circuits are required to be 20A on 12 AWG wire per NEC 210.11(C)(1) and (2) because those areas see higher-draw plug-in appliances.
Can I upsize a breaker if my appliance draws more current than expected?
Only if the wire gauge already installed supports the higher breaker rating per NEC 240.4(D) and 310.16. You cannot simply install a larger breaker on existing wire — 12 AWG copper, for example, is capped at 20A regardless of the breaker installed.
What breaker size do I need for a sub-panel?
It depends on the sub-panel's total connected load and the feeder wire size. Common residential sub-panel feeders run 60A on 6 AWG copper or larger, but the exact breaker and wire size must be calculated from the sub-panel's actual demand load.
Conclusion
This chart covers the breaker sizes you'll encounter in the vast majority of homes, but it's a starting reference, not a substitute for calculating your specific load. Always confirm against the appliance nameplate and, for anything beyond a simple lighting or receptacle circuit, run the numbers through a calculator or a licensed electrician.
Disclaimer: While our articles and tools are designed to align with the National Electrical Code, always check with local building inspectors and licensed electrical contractors before initiating physical installations.