Corrections and updates
What happens when a number here is wrong, and how the figures are kept current.
If you think something is wrong
Tell us, and if you are right it gets fixed and recorded here. Every figure on this site is meant to be checkable: each page names its sources and the date they were last verified, so a disagreement can usually be settled by looking at the same gov.uk page.
That matters more here than on most sites. A confidently wrong number about someone's pay is worse than no number at all.
How the figures stay right
Three things, all of which happen before anything is published.
Rates are fetched, not remembered
Every rate comes from gov.uk or the ONS and goes into a dated file with its source URL attached. Nothing is typed from memory. When a page says a figure was checked on a date, that is the date someone loaded the source and compared it.
The maths is tested against published figures
The calculations are pinned to numbers HMRC publishes, including their own worked examples. The National Insurance behind the take-home pay calculator is tied to the £58.66 that gov.uk gives for someone earning £1,000 a week. Where no worked example exists, the expected answer is derived by hand and the derivation is written next to the test, so it can be argued with.
The tests are checked for being able to fail
A test suite that always passes proves nothing. Before a change ships, rates are deliberately altered to wrong values to confirm the tests go red. That has caught real problems, including a tolerance that was right for money and useless for a percentage, which let a wrong National Insurance rate through unnoticed.
What changes in April, and what to watch
Tax rates change at the start of each tax year on 6 April. The National Minimum Wage changes on 1 April, five days earlier, which is why it is held separately. Until a page shows a verification date inside the current tax year, treat it as last year's figures.
Student loan thresholds are the ones most likely to drift: gov.uk publishes them without a tax year attached, so they cannot be verified from the page date alone and have to be re-checked deliberately each April.
What this site does not do
It does not give advice, it cannot see your payslip, and it does not know anything unusual about your circumstances. Every tool states its assumptions on its own page. Where something is left out, that is said plainly rather than quietly ignored.
Corrections made so far
None yet. The site launched in July 2026. When a correction is made it will be listed here with the date and what changed, including corrections nobody noticed but us.
Last reviewed 16 July 2026