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Both calculators run independently — change the inputs on either side to compare results.
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.
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.
Key differences
| Circuit Breaker Size Calculator | Circuit Breaker Sizing Calculator | |
|---|---|---|
| Category | Electrical Home | Electrical Home |
| Inputs required | 4 | 3 |
| Result | Minimum Breaker Size (amps) | Required Breaker Size (amps) |
| What it does | 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. | 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. |