thetaxdebtresolution.com publishes free calculators and plain-English guides for people who owe tax they cannot pay in full.
How we build each tool
- Every rate, threshold, penalty and deadline is taken from the tax authority's own published guidance or the legislation, and each tool lists those sources.
- Interest rates that change during the year are shown with the period they apply to. If a figure could not be confirmed it is left out rather than guessed.
- Each calculation has automated tests with worked examples checked by hand.
- Figures were last reviewed on 18 October 2026.
What the tools are not
They are estimates. Tax authorities decide each case on its own facts, and some programs involve judgement that no calculator can make. We are not affiliated with any tax authority and we do not provide tax, legal or financial advice.
Your privacy
Calculations run entirely in your browser. We do not ask for your name, contact details or tax identifiers to show a result.