Lighting Load Calculator
Estimate how much lighting a circuit may practically support based on breaker size, voltage, and fixture wattage.
Use this as a quick planning tool for lighting counts, available watts, and basic circuit headroom.
Enter the lighting details to estimate how much room is left on the circuit.
Estimated result
Usable circuit watts
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Existing load
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Available watts
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Estimated number of lights allowed
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Status
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Run the calculator to estimate how many fixtures may fit on the circuit comfortably.
Practical note
Continuous lighting loads are commonly planned more conservatively than short-term loads.
This tool is meant to help you understand usable circuit capacity, not to act as a full code calculation engine.
This calculator is a practical planning reference only. Actual circuit capacity depends on the installation, connected equipment, lighting characteristics, and applicable code requirements.
Related problems and reference
Planning and safety note
This content is for general learning and planning. Always verify work against current NEC requirements, manufacturer instructions, and local code rules. If you are unsure or see heat, sparks, burning smell, repeated trips, or damaged wiring, contact a licensed electrician.