How to use Electricity Bill Calculator
This electricity bill calculator estimates the running cost of any appliance or your whole home from power draw, hours of use and your electricity rate. See the cost per hour, day, month and year, and compare appliances to find what is driving your bill. It turns abstract kilowatt-hours into real money so you can target the biggest savings.
- Enter the appliance power in watts (or kilowatts).
- Set how many hours per day it runs.
- Enter your electricity rate (cost per kWh).
- Review the daily, monthly and yearly running cost.
- Compare appliances to find the biggest energy users.
Your data never leaves your device — 100% private processing.
How appliance running cost is calculated
Energy used (kWh) = power in kilowatts × hours of use. Cost = kWh × your rate per kWh. A 1,500 W heater running 5 hours uses 7.5 kWh per day; at $0.20/kWh that is $1.50 a day, or about $45 a month. Always-on devices and heating/cooling usually dominate a bill far more than small electronics.
| Appliance | Power | Use | Daily cost |
|---|---|---|---|
| LED bulb | 10 W | 5 h | $0.01 |
| Refrigerator | 150 W | 24 h | $0.72 |
| Space heater | 1,500 W | 5 h | $1.50 |
Cutting your electricity bill
Focus on the biggest, longest-running loads: heating, cooling, water heating and refrigeration. Reducing runtime, upgrading to efficient models, and shifting use to off-peak hours where time-of-use rates apply all lower the bill. Standby ("phantom") loads add up too — this calculator helps you quantify each before you act.
Worked examples
Space heater
Inputs: 1,500 W · 5 h/day · $0.20
Result: $1.50/day · ~$45/mo
Refrigerator
Inputs: 150 W · 24 h · $0.20
Result: $0.72/day · ~$22/mo
Glossary
- kWh
- Kilowatt-hour — one kilowatt of power used for one hour; the unit you are billed for.
- Watt
- A unit of power; 1,000 watts equal one kilowatt.
- Rate
- The price you pay per kilowatt-hour of electricity.
- Standby load
- Power drawn by devices left plugged in but not actively used.
Related reading
Frequently Asked Questions
Why use Electricity Bill Calculator?
- Converts any appliance's watt rating and daily hours into precise monthly and annual costs
- Side-by-side appliance list ranks devices by running cost to show where money is going
- Accepts any per-kWh rate including time-of-use tariff values you enter manually
- Shows daily, monthly and annual costs simultaneously so you can judge short and long-run impact
Common use cases
- Find out how much a 1,500 W space heater running six hours a day adds to the monthly bill
- Compare the annual running cost of an old refrigerator versus a new energy-efficient model
- Estimate the electricity cost of a permanently installed home-office setup before committing
- Identify the highest-cost appliance in the home to prioritize energy-efficiency upgrades
- Calculate whether unplugging always-on standby devices produces a meaningful annual saving
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