About Sumcheck
Sumcheck is an independent, ad-supported site with fast, clear UK financial calculators — day-rate to salary, debt payoff, mortgage affordability, and more to come. Every tool aims to answer one specific money question well, without asking for an account, an email address, or any personal details first.
What we're trying to do differently
- No sign-up, ever. Every calculator works instantly. If a tool remembers your inputs between visits, that's stored only in your own browser — never on our servers.
- Show the working. Each calculator includes a plain-English explanation of the method behind the numbers, not just a black-box result.
- Current UK rates. Tax bands, National Insurance thresholds, stamp duty rates, and similar figures are kept up to date with the current UK tax year.
What this site isn't
Sumcheck isn't a financial adviser, an accountant, or a regulated provider of financial advice. Every calculator produces an estimate based on simplified, general assumptions — useful for planning and comparison, not a substitute for advice tailored to your actual circumstances. See our Terms of Use for the full picture.
How the site makes money
Sumcheck is supported by advertising, which keeps every calculator free to use with no sign-up. Ads never affect the numbers a calculator shows you — the results are always calculated the same way regardless of what's advertised on the page.
Get in touch
Spotted something that looks wrong, or have a suggestion for a new calculator? We'd like to hear it — hello@sumcheck.co.uk, or see the Contact page.