Electrical Breaker & Wire Size Calculator

Calculate Correct Conductor Size and Breaker Rating Using CEC or NEC

This breaker and wire size calculator helps electricians quickly determine the correct conductor size and circuit breaker rating based on electrical load. The calculator supports both Canadian Electrical Code (CEC) and National Electrical Code (NEC) standards and uses ampacity tables to recommend the appropriate wire gauge for safe installations.

Load Amps

Input Distance

Results:

Code Basis:

Breaker Size:

Wire Size:

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Min. Recommended wire size:

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Ampacity Used:

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Voltage Loss/Drop (%):

Pass/Fail Result:

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Suggested Correction:

Job Name

Calculator Summary/Disclaimer

This electrical breaker and wire size calculator estimates breaker size, conductor size, and voltage drop based on user inputs. Calculations use standard electrical formulas and typical conductor ampacity values used in the NEC and CEC.

Voltage drop calculations assume one-way conductor length and use a recommended branch circuit design limit of approximately 3%. Results should always be verified against the applicable electrical code and local regulations.