Richard Barker is the founder and editor of Online Calculators. He has spent over a decade building specialist UK web tools and reference resources, with a particular focus on getting the underlying figures right.
Every rate-sensitive calculator on this site - income tax, National Insurance, stamp duty, road tax and the rest - is checked by Richard against the current HMRC, DVLA and official guidance for the 2026/27 tax year. Where a calculator relies on a formula or a published standard, the method is set out in full on the page so you can see exactly how a result is reached.
The aim of the site is simple: calculators that are correct for the UK, explained plainly, with no sign-up and no clutter.
Editorial approach
Every calculator on Online Calculators is published with its method shown. For rate-sensitive tools, the figures are checked against the relevant official source - HMRC for tax and National Insurance, DVLA for vehicle tax, and published NHS or standards guidance for health and measurement tools.
When a rate changes, the affected calculators are updated and their review date refreshed. Corrections raised by readers are investigated and, where valid, fixed promptly. The aim is a site that people can rely on.
Contact
To raise a correction or suggest a calculator, see the contact page.