This site publishes free, no-signup calculators for UK contractors, landlords and small businesses — starting with the Construction Industry Scheme, statutory late payment interest, and letting agent fees. Every tool is built to reflect current HMRC and statutory guidance, and reviewed periodically as rates change.
Most calculators like these are buried in dense guidance documents or paywalled tools. The aim here is simple: enter your numbers, get a straight answer, with a plain-English explanation of the rule behind it if you want to check the working.
Figures and thresholds are checked against HMRC and legislation.gov.uk guidance at the time each tool is built or updated. Rules change — always confirm anything you're relying on for a tax return, invoice, or legal claim against the original government source, or with a qualified accountant or solicitor.
Questions, corrections, or a tool you'd like to see: budklair@yahoo.co.uk