How Digital Adaption builds and checks its free calculators and templates: who writes them, where the rates come from and how to report an error.
The calculators under Free tools and the templates under Downloads are free to use. This page says who writes them, where the numbers come from, how they are checked and how to tell us when something is wrong.
The tools and templates are written and maintained by Matty Hatton, the founder of Digital Adaption, a data migration and reporting consultancy based on the Wirral. His background is on the About page. There is no separate editorial team, and nobody pays to be mentioned or linked.
Tax rates, thresholds and allowances are held in one rates table, and the calculators and workbooks are built from it. The table is checked by hand against the official source for each figure: GOV.UK and HMRC for tax, National Insurance, VAT and Making Tax Digital figures, and the Bank of England for Bank Rate. The table was last checked on 8 October 2026 and covers the 2026/27 tax year. Template pages show the date their figures were last checked.
Template pages list the official guidance they were checked against in a Sources section at the bottom of the page.
Once a day a script reads the numbers inside every live calculator and compares them with the rates table. It reports any number that sits close to a real rate without matching it, which is what an out of date or mistyped rate looks like, and any rate a calculator is meant to apply but no longer contains.
The check has limits. It compares the calculators with the rates table; it cannot tell whether the table itself is right, which is why the table is checked by hand. It covers the calculators, not the downloadable workbooks and documents, which are checked by hand when rates change and when an error is reported.
The tools and templates give general information and a starting point. They are not tax advice, legal advice or health and safety advice, and they do not know your circumstances. Check the official guidance linked from each page, and use a qualified accountant, solicitor or competent safety adviser for decisions that matter. The risk assessment and fire risk assessment templates are for simple, low-risk situations and do not replace a competent assessor.
If you find an error, email matty@digitaladaption.co.uk with the page address and what looks wrong. We check the report against the official source, correct the page or file if it is wrong, and record the correction in the changelog below.