Electricity Cost Calculator
Work out how many units (kWh) an appliance uses and what it costs to run, from its wattage, hours of use a day and your price per unit.
- Cost for the period
- –
- Units used (kWh)
- –
- Cost per day
- –
How it is calculated
- Daily units (kWh) = watts × number of appliances × hours per day ÷ 1,000
- Units for the period = daily units × days
- Cost = units × price per unit
Worked example
A 1,500 W air conditioner running 8 hours a day for 30 days, at 50 per unit.
| You enter | |
|---|---|
| Power | 1,500 W |
| Number of appliances | 1 |
| Hours used per day | 8 h |
| Days | 30 days |
| Price per unit (kWh) | 50 |
| You get | |
| Cost for the period | 18,000 |
| Units used (kWh) | 360 kWh |
| Cost per day | 600 |
1 × 1,500 W for 8 hours a day uses 360 kWh over 30 days, costing 18,000.
Sources and checks
Last checked: 15 October 2026. This calculator passes 5 automatic tests before every release.
Your numbers never leave your device: the calculation runs in your browser and nothing you type is sent or stored.
Appliances often draw less than their label power (thermostats and inverters cycle on and off). Your bill also includes fixed charges and taxes, which are not included here. Results are estimates for information only and are not financial, tax or legal advice. Check important figures with a qualified professional before you act on them.