Last Updated: 13 March 2026
Why this site exists
I built UKFinanceTools for a simple reason: I couldn't find a calculator I trusted.
Most financial tools on the web fall into two categories: simple click-bait farms that lack nuance, or complex portals hidden behind paywalls and sales funnels. As a business owner, developer and investor, I wanted something better—a tool that respects the user's intelligence and their privacy.
There is no "sales team" here. Just code, maths, and the current UK tax laws.
Data Integrity & Methodology
Accuracy is the primary metric of this site. To ensure the results you see are reliable, I adhere to a strict "Glass Box" development standard:
- Source of Truth: Every calculation is cross-referenced strictly against HMRC Internal Manuals, Legislation.gov.uk, or the relevant statutory authority for a given tool. We do not use third-party summaries.
- Unit Testing: The logic behind our tools (e.g., National Insurance thresholds, Dividend allowances) is subjected to automated testing against known edge-cases to prevent regression.
- Privacy by Design: Calculations happen in your browser or via ephemeral sessions. We do not store your confidential information such as salary, tax codes, or net worth in a database.
About the Author
Graham Gourlay is the founder of UKFinanceTools. He has spent his career in programme and project management within the financial services sector, and manages his own investment portfolio — which means he navigates the CGT annual allowance, IHT planning, pension changes, and the Scottish income tax divergence as a taxpayer, not just as a writer.
The guides and calculators on this site are built to the standard he wanted for himself: every figure sourced to HMRC or primary legislation, no invented caveats, and no paywalls.
See the methodology in action.
Calculate My Tax Safely