Appliances

Browse 14 appliances tools. Opening Lighting Circuit Load Calculator.

Appliance Daily CostCalculate daily electricity cost for any appliance from watts and runtime.Use this to find out what any appliance adds to your daily bill.
Appliance Monthly EnergyConvert appliance watts and daily use into monthly kWh.Use this to spot which devices drive your monthly usage up.
Energy Consumption CalculatorEstimate total kWh from watts, hours per day, and number of days.Use this to forecast usage over any period and catch bill surprises early.
Electric Heater Cost CalculatorEstimate heating cost from wattage, run hours, days, and electricity rate.Use this to budget your winter heating before the bills arrive.
Air Conditioner Energy Cost CalculatorEstimate monthly AC electricity cost from watts, daily hours, and rate.Use this to know what summer cooling really costs and plan your usage.
Refrigerator Energy Usage CalculatorEstimate refrigerator kWh and cost from wattage and electricity rate.Use this to see if your old fridge is quietly costing you money.
Crypto Mining Power CalculatorEstimate kWh and electricity cost for GPU/ASIC rigs by wattage and run hours.Use this to check your mining rig is actually profitable after electricity.
Vampire Power Cost CalculatorEstimate yearly electricity cost for TVs, chargers, and other devices drawing power in standby.Use this to find hidden standby costs and decide what to unplug.
Standby Power Waste CalculatorQuantify phantom load cost from devices left plugged in 24/7 on standby.Use this to see what always-on devices cost you over a full year.
Generator Fuel Consumption CalculatorEstimate fuel use per hour and runtime from tank size at your load level.Use this to know how much fuel to stock before an outage or trip.
Heat Pump vs. Resistance Heat CalculatorCompare electric heating cost: resistance strips (COP 1) vs. heat pump COP.Use this to see how much a heat pump would cut your heating bill.
Whole House Energy Budget CalculatorSum daily kWh by category and estimate monthly and annual electricity cost.Use this to build a full home energy budget and find where to cut costs.
Lighting Circuit Load CalculatorSum fixture watts, compute circuit amps, and check breaker utilization against the 80% continuous-load guideline.Use this to add lights safely without overloading the circuit.
AC Efficiency & Inverter Savings CalculatorCompare on/off vs. inverter air conditioner monthly electricity cost, energy savings, and purchase payback period.Use this to decide if upgrading to an inverter AC pays off for you.

Lighting Circuit Load Calculator

Inputs

Adjust values to update results live

Number of fixtures (#)

Power per fixture (W)

Nameplate or LED driver rating

Circuit load

Enter fixtures, watts, voltage & breaker

Total lighting load

Enter values above

Breaker utilization

Enter values above

Share this calculator

How to use the Lighting Circuit Load Calculator

The Formula

Lighting circuits run for hours—often treated as continuous loads. Loading a breaker past 80% of its rating risks heat, nuisance trips, and dimming when other loads share the neutral. Count every luminaire on the branch before you close the drywall.

Practical Example

Total W = fixtures × W each. Amps = W ÷ V. Utilization % = 100 × amps ÷ breaker amps. Compare to 80% of breaker amps (12 A on a 15 A breaker, 16 A on 20 A) for continuous-load headroom.

About Lighting Circuit Load Calculator

Total W = fixtures × W each. Amps = W ÷ V. Utilization % = 100 × amps ÷ breaker amps. Compare to 80% of breaker amps (12 A on a 15 A breaker, 16 A on 20 A) for continuous-load headroom.

LED retrofits cut amps dramatically—do not size new breakers using old incandescent nameplates on the same fixture count. Use actual driver watts from cut sheets.

Q: 240 V lighting? A: Enter line voltage the circuit uses; amps = W ÷ V. Q: Dimming? A: Plan for rated wattage, not dimmed level. Q: Code compliance? A: Planning tool—follow local NEC or IEC and licensed design for permits.

Related tools

Watts to AmpsConvert electrical power (watts) to current (amps) at a given voltage.Use this to check a device won't overload your circuit or blow a fuse.
Residential AC Voltage Drop CalculatorCalculate AC voltage drop in home wiring from supply voltage, amps, cable length (m), and AWG or mm² copper size.Use this to make sure far-away outlets still deliver full voltage to your devices.
LED vs. Incandescent ROI CalculatorEnergy and bulb replacement savings when matching lumens with lower watts.Use this to see the full savings of switching your lighting to LED.
Appliance Daily CostCalculate daily electricity cost for any appliance from watts and runtime.Use this to find out what any appliance adds to your daily bill.

How to use the Lighting Circuit Load Calculator

The Formula

Practical Example

Total W = fixtures × W each. Amps = W ÷ V. Utilization % = 100 × amps ÷ breaker amps. Compare to 80% of breaker amps (12 A on a 15 A breaker, 16 A on 20 A) for continuous-load headroom.

About Lighting Circuit Load Calculator

Total W = fixtures × W each. Amps = W ÷ V. Utilization % = 100 × amps ÷ breaker amps. Compare to 80% of breaker amps (12 A on a 15 A breaker, 16 A on 20 A) for continuous-load headroom.

LED retrofits cut amps dramatically—do not size new breakers using old incandescent nameplates on the same fixture count. Use actual driver watts from cut sheets.

Appliances

Green Home

Backup

EV Charging

Cost

Pool

TOU