Electricity consumption calculator (kWh)
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This electricity consumption calculator converts any wattage into kWh per day, month and year — the number your bill actually charges for — and anchors it with typical draws across the cooling categories we review.
Formula: kWh/day = W × h ÷ 1,000; month = ×30; year = ×365 at the same daily use. Pair with the energy cost calculator to price it.
Typical draws by category
| Personal evaporative cooler | 5–60 W (e.g. Coolizi: 45 W claimed) |
|---|---|
| Personal compressor unit | ≈300–350 W (Coolzy class) |
| Conventional compressor portable | 800–1,500 W |
| Electric heat mode on 2-in-1 devices | Hundreds of watts — check before winter reliance |
Why kWh, not watts, decides the bill
Watts describe the moment; kWh describe the month. A big unit used rarely can cost less than a small one running around the clock — which is why every FreezAir review discusses realistic hours, not just the label. Price your kWh in one click at the energy cost calculator.
Frequently asked questions
How is electricity consumption calculated?
kWh = watts × hours ÷ 1,000. This electricity consumption calculator multiplies that daily figure across a month and a year so spec-sheet watts turn into bill-sheet numbers.
How much electricity does a portable AC use?
Conventional compressor portables typically draw 800–1,500 W while cooling — call it 8–12 kWh over a hot day. Personal compressors sit around 300–350 W; evaporative coolers run on 5–60 W.
kW vs kWh — what is the difference?
kW is speed, kWh is distance. A 1.2 kW unit running for 3 hours consumes 3.6 kWh — the bill charges for the kWh.
How do I find a device’s wattage if unlisted?
Check the label plate for volts × amps (our power calculator does the conversion), or use a plug-in energy meter for the ground truth.