Appliance electricity cost calculator
Calculate the hourly, daily, monthly, and annual cost of any electrical appliance using its wattage, runtime, and your own electricity rate.
Worked calculation
A complete any appliance example
0.120 kW is multiplied by scheduled time and the 100% active-runtime assumption. The inputs are examples, not claims about every device. Replace each one with the label, meter reading, schedule, and tariff that apply to you.
Cost = watts ÷ 1,000 × active hours × electricity rate120 W · 4 hours/day · 7 days/week · 100% active
- Monthly energy
- 14.6 kWh
- Monthly cost
- US$2.62
- Annual cost
- US$31.45
From watts to your bill
How to calculate electricity cost
A 1,000 W appliance running for two hours uses 2 kWh. At an illustrative $0.20/kWh, that is $0.40 per day or $12 over 30 days. Replace the example rate with your own rate; it is not a current tariff.
1,000 ÷ 1,000 × 2 × 30 × $0.20 = $12The calculator uses an average month of 52 weeks ÷ 12. A calendar-month calculation may differ slightly.
Appliance cost versus a complete electricity bill
Add each appliance’s kWh before applying your bill’s rates. Include fixed charges separately when estimating a whole bill. For time-of-use or tiered pricing, calculate each rate band separately rather than multiplying everything by one average.
Find the right rate on your bill · Singapore electricity calculator · UK electricity calculators
Transparent method
The calculation
Cost = watts ÷ 1,000 × active hours × electricity rateUse this general model for devices with reasonably stable power draw, including televisions, computers, kitchen appliances, pumps, lighting, and workshop tools.
Read the full methodology →Sensitivity check
Run three scenarios.
Light useReduce daily runtime to model occasional use.
Typical useUse your normal weekly schedule and the label wattage.
Heavy useIncrease runtime or quantity to test a demanding month.
Use the result well
What can change the answer?
- Labels may show maximum rather than typical power.
- Time-of-use tariffs require separate peak and off-peak runs.
- Fixed utility charges are not attributed to one appliance.
Calculation standards
Visible inputs. Reproducible results.
WhoPowerCost Lab's research desk maintains the formulas, market notes, and worked examples.
HowEnergy, tariff, and behavioural assumptions stay separate so readers can replace one input without hiding the others.
WhyThe page exists to answer an operating-cost decision. Advertising never changes a formula, default, or recommendation.