kWh Cost Calculator

Enter how many kilowatt-hours you used and what you pay per kWh to see the cost of that energy.

How it works

A kilowatt-hour is the usual billing unit. If you already know the kWh (from a meter, a charger session or a bill line) and the unit rate, cost is their product. 12 kWh at 0.25 per kWh is 3.00. This page does not convert watts and hours — use Electricity Cost when you start from power and duration.

Formula

Cost = kWh × price per kWh

Worked examples

  • 12 kWh at 0.25 / kWh 3.00
  • 10 kWh at 0.20 / kWh 2.00

Useful notes

  • No standing charge, tax or time-of-use split.
  • Negative energy or price is rejected.

FAQ

What is a kWh?
One kilowatt running for one hour, or any equivalent (500 W for two hours, and so on).
Where do I find my price per kWh?
On your electricity bill or tariff sheet. Use the unit rate, not the standing charge.
How is this different from the electricity cost tool?
This starts from kWh you already know. The other starts from watts or kW and hours.

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