Trust centre
A calculator is only worth using if you can check it. Everything that decides a result on this site is documented: the rates, the assumptions, the exclusions and the review dates.
Rates currently in use
- 2025/26 (current) — reviewed 22 August 2026
- 2024/25 (previous) — reviewed 22 August 2026
Calculation engine v1.0.0
Our commitments
- Every result is labelled as an estimate, with its assumptions in view.
- We never present a calculation as tax advice.
- Figures you enter stay in your browser.
- Commercial placements never influence a calculation or a ranking.