Versioned JSON, not memory
Tax bands, thresholds, and contribution rates live in country-specific data files in this project. Calculators read those files; we do not invent rates from memory when building engines.
Each tax tool page shows the tax year, last verified date, and a link to the official authority (for example IRS, HMRC, ATO, FBR, CRA, or German BMF).
What TODO_VERIFY means
Until a data file is checked against the current official publication, fields may be placeholders marked for verification. Results remain educational estimates even after verification — personal circumstances and mid-year law changes can still differ.
If you spot an outdated figure, use the contact page so we can update the file and re-check the source.
Frequently asked questions
Can I rely on a calculator for my tax return?
No. Use official software, a qualified adviser, or the tax authority’s tools for filings. Our calculators are for learning and rough planning only.
Estimates and explanations only — not financial advice. See our disclaimer.