Tools

Free calculators that use official data and your own electricity price. Nothing to sign up for.

• Running cost calculatorWhat any appliance costs per hour, month and year, from its watts.
• Generator size calculatorThe running and starting watts you need for the things you want to run at once.
• Replace or keep?How much a new, efficient appliance saves, and how long it takes to pay for itself.
• Power station checkerWill a portable power station run your appliances, for how long, and can it handle the start-up surge?

Which one do I need?

Want to know what something costs to run? Use the running cost calculator, or find the appliance on the home page for typical figures from official data. Planning for a power cut, a campsite or a van? The generator size calculator and the power station checker tell you what will run, and for how long. Thinking about a new fridge, freezer or dryer? Replace or keep shows the yearly saving and how long it takes to pay back.

Every calculator works in your own currency, remembers your country and electricity price, and runs in your browser with nothing to sign up for.