Electricity Cost Calculator
Work out what an appliance costs to run.
Cost per day
£1.00
- Energy used per day
- 4 kWh
- Monthly cost
- £30.44
- Annual cost
- £365.00
v1.0 · Reviewed September 2026
How this is worked out
Energy per day is watts ÷ 1,000 × hours used. Cost is that × the price per kWh. The monthly figure uses 30.44 days, the average calendar month, and the annual figure uses 365 days.
Worked example
- 2,000 W
- 2 hours a day
- 25p per kWh
4 kWh a day × 25p
£1.00 a day, £365.00 a year
Assumptions and limits
- Assumes the appliance draws its rated power the whole time it is on. Fridges, washing machines and anything thermostatically controlled cycle on and off, so real use is lower.
- Uses the unit rate only. The daily standing charge is not included, because it applies whether or not the appliance runs.
- Assumes the same usage every day of the year.