That always-on gaming PC, the garage freezer from 1997, the space heater you’re emotionally attached to — every appliance has a monthly price tag. The Gizmo 421 Electricity Cost Calculator adds up what each one really costs to run, in watts, hours, and dollars.
| Appliance | Watts | Hours/day | Cost | |
|---|---|---|---|---|
| — | ||||
| — |
Wattage is usually on the appliance label or its power brick. Check your utility bill for your exact rate — the US average is around $0.15–0.17 per kWh.
Each row shows its own monthly cost as you type, and the totals line adds up daily kWh plus monthly and yearly costs across everything. Add the fridge, the grow lights, the aquarium pump — anything with a wattage label. The formula is the one your electric company uses: watts times hours divided by 1000 gives kilowatt-hours, and kilowatt-hours times your rate gives money.
How much does it cost to run a 1500W heater? At 3 hours a day and $0.15/kWh, about $20 a month — heaters are usually the loudest thing on the bill. Where do I find my appliance’s watts? On the label near the power cord, the power brick, or the manual; if it lists amps, multiply by 120 (US voltage). What’s a kWh? 1000 watts running for one hour. A 100W bulb burning 10 hours uses 1 kWh. Is my rate right? Check your bill — the default 15 cents is a reasonable US average but rates vary a lot by state.