Cut your household bills

Free calculators that show what things really cost, so you can decide where to save. No sign-up, nothing to install, and every figure comes with its source.

Energy

Appliance running cost calculatorWhat your kettle, shower, tumble dryer or heater costs per use, per week and per year.NI electricity cost calculatorCompare Northern Ireland tariffs, standing charges included, and see what switching saves.Heating oil calculatorPrice per litre, yearly cost and how long a fill lasts in winter and summer.

Why use these

Most money-saving advice tells you to switch things off. These tools show you which switches are worth it. A 9.5 kW electric shower and a phone charger are not the same problem, and seeing the numbers side by side makes the choice easy.

Prices change often. Each calculator shows the default price it uses, where it came from and when it was last checked, and you can always type in the figure from your own bill.

Northern Ireland is different

If you live in Northern Ireland, much of the energy news you read does not apply to you. The Ofgem price cap covers Great Britain only, and the 0% VAT on electricity from October 2026 to March 2027 does not apply here either. The NI calculators above are built around how bills actually work in Northern Ireland.

Last checked: 4 October 2026.

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