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Electrical Home
Circuit Breaker Sizing Calculator
Determine the correct circuit breaker amperage for any electrical circuit using NEC load classification rules. Use it when designing new circuits or upgrading panels for continuous, non-continuous, and motor loads.
Fill in the required fields to see your result.
Electrical Home
Circuit Breaker Size Calculator
Determine the correctly sized circuit breaker for any electrical load, accounting for continuous versus non-continuous use, ambient temperature, and safety margins. Use it before wiring a new circuit or replacing a breaker.
Fill in the required fields to see your result.
Key differences
| Circuit Breaker Sizing Calculator | Circuit Breaker Size Calculator | |
|---|---|---|
| Category | Electrical Home | Electrical Home |
| Inputs required | 3 | 4 |
| Result | Required Breaker Size (amps) | Minimum Breaker Size (amps) |
| What it does | Determine the correct circuit breaker amperage for any electrical circuit using NEC load classification rules. Use it when designing new circuits or upgrading panels for continuous, non-continuous, and motor loads. | Determine the correctly sized circuit breaker for any electrical load, accounting for continuous versus non-continuous use, ambient temperature, and safety margins. Use it before wiring a new circuit or replacing a breaker. |