Electricity Cost Calculator
See how much an appliance costs to run. Enter its power, how long it runs each day, and your electricity price.
🔒 Saved only in your browser — these results never leave your device.
How to use this calculator
- Enter the appliance power and choose the unit (watts or kW).
- Enter the hours of use per day.
- Enter your price per kWh and currency symbol.
- Click Calculate for the cost per day, month and year.
How the cost is calculated
A device's power in watts divided by 1000 gives kilowatts (kW). Multiply by the hours it runs to get kilowatt-hours (kWh), the unit your utility bills you in. Multiply kWh by your tariff to get the cost.
Example
A 100 W bulb running 5 hours a day uses 0.5 kWh per day. At $0.15/kWh that is about $0.075 per day, roughly $2.28 per month and $27.38 per year.
Typical appliance wattages
| Appliance | Typical power |
|---|---|
| LED bulb | 8–12 W |
| Laptop | 30–65 W |
| TV | 50–120 W |
| Refrigerator | 100–200 W |
| Microwave | 800–1200 W |
| Electric kettle | 1500–2200 W |
| Air conditioner | 1000–2000 W |
| Water heater | 3000–4500 W |
Frequently asked questions
- How do I calculate my electricity cost?
- Energy (kWh) = power in kW × hours used; cost = energy × your price per kWh. Watts ÷ 1000 gives kW.
- How much does it cost to run a 1500 W heater?
- It uses 1.5 kWh per hour. At $0.15/kWh that is about $0.23 per hour, or roughly $1.13 for 5 hours a day.
- What is a kWh?
- A kilowatt-hour is the energy used by a 1000 W appliance running for one hour — the unit your utility bills you in.
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