Circuit Load
Check how loaded a branch circuit is from its outlets.
About Circuit Load
Multiplying the outlets by their expected wattage gives the total load, converted to amps and compared to the breaker rating as a percentage. A circuit is meant to run comfortably below its breaker rating, so checking the percentage protects against tripping and overload.
Formula
Circuit Load
Load % = (outlets x watts / voltage) / breaker rating x 100
- breaker rating
- Nominal amp rating of the circuit
Worked example
With the default values below, Circuit Load returns Load Percentage of 60.0%. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Breaker ratingminimum 1 A
- 20 A
- Voltageminimum 1 V
- 120 V
- Outletsminimum 1
- 8
- Watts per outletminimum 0 W
- 180 W
Results
- Total Load
- 1,440 W
- Total Amps
- 12.00 A
- Load Percentage
- 60.0%
- Remaining Capacity
- 8.00 A
Step by step
- 1Values used
- 2Circuit Load
- 3Load Percentage= 60.0
- 4Total Load= 1,440 W
- 5Total Amps= 12.00 A
- 6Remaining Capacity= 8.00 A
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Circuit Load calculated?
Load % = (outlets x watts / voltage) / breaker rating x 100 Multiplying the outlets by their expected wattage gives the total load, converted to amps and compared to the breaker rating as a percentage.
Why does Circuit Load matter?
A circuit is meant to run comfortably below its breaker rating, so checking the percentage protects against tripping and overload.
What values do I need to enter?
This calculator takes 4 inputs: Breaker rating, Voltage, Outlets, Watts per outlet. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.