FreeCalculator exists to give people in the UK accurate, understandable answers about their money. Every calculator and guide on this site follows the standards below. Where we fall short of them, we want to know — see corrections.
Who reviews the content
All calculators and guides are researched, built and reviewed by the FreeCalculator editorial team. We are an independent publisher: we are not a lender, broker or adviser, we do not sell financial products, and nothing on this site is financial advice. We describe how the rules work and let you test your own numbers — decisions, and advice where you need it, belong with you and a qualified adviser.
Where our figures come from
Every tax band, threshold, rate and allowance used on this site is taken from an official UK source — primarily GOV.UK and HMRC, alongside the Bank of England for interest-rate context, Revenue Scotland and the Welsh Revenue Authority for devolved property taxes, and the Money and Pensions Service (MoneyHelper) for consumer guidance. Each calculator page cites its sources and shows the date its figures were last verified.
All rates live in a single, version-controlled configuration with a verification date against each figure. When a rate changes, it changes in one place and every affected calculator updates together — there is no page-by-page copy of the rules to drift out of date.
How calculators are tested
- Calculation engines are built from the published rules (not reverse-engineered from other calculators) and are covered by an automated test suite that runs before every release.
- Results are checked against published examples — HMRC worked examples, official calculators and lender illustrations — before a calculator ships.
- The worked examples in our guides are generated by the same engines as the calculators, so the article and the tool can never disagree.
How often content is reviewed
Rates and thresholds are reviewed at every fiscal event that can change them: the start of the tax year in April, Budgets and fiscal statements, and Bank of England rate decisions. Each calculator shows a “last updated” date on its rates table, and each guide shows a “last reviewed” date beneath its heading. If a date looks stale after a major announcement, the figures are under review.
Advertising and affiliate policy
- Advertising is always clearly labelled and never appears above or inside a calculator.
- Advertising and commercial partnerships have no influence on calculator results, guide content, or the order in which tools are shown. The maths answers to GOV.UK, not to advertisers.
- If we link to a partner and may earn a commission, the section is labelled with an advertiser disclosure, and it costs you nothing.
- Analytics and advertising cookies load only with your consent — see the cookie policy.
Corrections
If you believe a figure, calculation or statement on this site is wrong, email hello@freecalculator.co.uk with the page address and what you believe is incorrect. We check reports against the official sources above, fix confirmed errors promptly, and update the page’s review date. Material corrections are noted on the affected page.
The small print
Results are estimates for guidance, based on the rules and rates in force at the review date shown. Individual circumstances vary, and providers apply their own criteria — always confirm figures with the official source or a qualified adviser before acting. See our terms of use and methodology for more.