Breaker Size Calculator
Free calculate the correct circuit breaker size based on load current, wire gauge, and application requirements.
Input Parameters
Total current draw of the circuit
Recommended: 25% for safety margin
Results
Enter parameters to calculate breaker size
Breaker Sizing Guidelines
Standard Rule
Breaker size = 125% of continuous load current
Must not exceed wire ampacity rating
Common Breaker Sizes
- • 15A, 20A, 30A, 40A
- • 50A, 60A, 70A, 80A
- • 100A, 125A, 150A, 200A
- • Always round up to next standard size