About Numwise
Work out the numbers before you buy.
Who we are
Numwise is run by Steven.
Where our figures come from
We use official sources wherever they exist, such as Ofgem for energy prices and GOV.UK and HMRC for tax. Each calculator lists its sources and the date we last checked them.
How often we update
Prices that change on a schedule, like the energy price cap, are updated when the new figures are published. Every page shows its last updated date.
Limits
Our results are estimates to help you plan. Your own costs depend on your tariff, your home and how you use things.