Electricity & Appliance Cost Calculator
See what any appliance actually costs to run — pick a common one below or enter its wattage yourself, add how long you use it, and get a real cost per hour, day, month, and year.
Estimate assumes steady power draw for the hours entered. Devices with a compressor or thermostat (fridges, AC units) cycle on and off, so real-world cost is usually somewhat lower than this — see the FAQ.
How this is calculated
Electricity is billed in kilowatt-hours (kWh) — a 1,000-watt device running for one hour uses exactly 1 kWh. Watts and kWh are the same units worldwide, so this math doesn't change by country — only your local rate and currency do.
cost = kWh used × rate per kWh
Worked example: a 1,500W space heater run 4 hours a day at $0.17/kWh: (1500 ÷ 1000) × 4 = 6 kWh/day, × $0.17 = $1.02/day — about $31/month or $372/year if run every day at that rate.
Frequently asked questions
How much does it cost to run an appliance for 8 hours?
Enter its wattage (or pick it from the list), set hours used to 8, and enter your electricity rate — the calculator shows the cost per day instantly, which in this case is your 8-hour cost.
Where do I find my electricity rate?
Your rate per kWh is printed on your utility bill, usually per billing period. If you don't have a bill handy, the 2026 U.S. average is roughly $0.17–0.18/kWh, though it varies a lot by state and country — use the currency selector above if you're outside the U.S., and enter your own local rate either way.
Why is my real bill lower than this estimate?
Appliances with a compressor or thermostat — refrigerators, air conditioners, some heaters — don't draw full power the entire time they're plugged in; they cycle on and off to maintain a temperature. This calculator assumes the wattage you enter is drawn for the full hours you specify, which is accurate for simple resistive devices (heaters, hair dryers, dryers) and a reasonable upper-bound estimate for cycling ones.
How do I find the exact wattage of my device?
Check the label on the device itself (often on the back or bottom) or its manual — it's usually listed in watts (W) directly, or as volts × amps, which you can multiply together to get watts.
What does it cost to run my PC or a space heater specifically?
This calculator works for any appliance, but for more precise presets see the PC electricity cost calculator (with GPU/CPU wattage options) or the space heater cost calculator (with common wattage settings and seasonal totals).