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Electrical Load Calculator

Add your appliances, enter wattage and daily usage hours to calculate electricity consumption, monthly bill and required MCB rating.

Appliance Wattage (W) Qty Hours/Day kWh/Day
Total Load
Watts
Daily Units
kWh/day
Monthly Units
kWh/month
Monthly Bill
Recommended MCB / Circuit Breaker
Recommended MCB
Current Draw
Full load current
At 80% diversity factor
Design current (×1.25)

kWh = Wattage × Hours per day × Days / 1000. A 1,500W AC running 8 hours/day for 30 days = 1500 × 8 × 30 / 1000 = 360 kWh/month. Each kWh = 1 unit on your electricity bill.

MCB current = Total watts / Voltage (230V). Multiply by 1.25 safety factor and select the next standard MCB size (6A, 10A, 16A, 20A, 25A, 32A, 40A, 63A). For 3,000W: 3000/230 = 13A × 1.25 = 16.3A → use 20A MCB.

Connected load is all appliances running simultaneously. Demand load applies a diversity factor (0.6-0.8 for homes) since not all appliances run at the same time. MCB sizing typically uses demand load rather than full connected load.