Understand the number before you calculate it.
Short practical guides to kWh, appliance running cost, home charging and reducing electricity use without hiding the formula.
How to calculate electricity cost from watts
Convert power and run time into kWh and then into cost.
FundamentalsWhat is a kilowatt-hour?
Separate power from energy and understand the unit used on electricity bills.
ExplainerWatts vs kWh explained
The difference between a rate of use and a quantity of energy, with worked examples.
FundamentalsHow electricity bills work in Europe
Unit rates, standing charges, taxes and levies, and which part a calculator can model.
BillingAverage electricity prices in Europe
Why published averages differ from your own rate, and how to read them properly.
PricesAppliance energy guide
Typical power draw by appliance type and how to find a figure you can trust.
ReferenceReduce an electricity bill with measured changes
Prioritise changes by kWh and usage patterns rather than guesswork.
SavingsBest ways to save energy at home
Which habits and upgrades genuinely move the number, ranked by impact.
SavingsEV home charging cost
Understand wall energy, charging losses and the tariff rate used in a home-charging estimate.
EVPrefer a calculator?
Browse all energy tools or use the whole-home energy budget to combine several appliances in one monthly plan.