Sources and periods
We link to tax authorities, social insurance agencies and legislation at the end of guides and calculators. Guide reference periods can differ from calculator periods. Use the year selector and scope notice for the calculation you need; a publication date is not necessarily an effective date.
Calculation and validation
Calculators run locally in your browser. Country-specific modules apply supported tax bands, contributions, caps, deductions and rounding rules. Automated regression checks and build checks help detect changes; they do not establish professional certification or guarantee every personal tax outcome.
Scope and limitations
Read the scope, exclusions and provisional-data notices before using a result. Some calculators cover selected regions or employee profiles only. Annual liability estimates may differ from payroll withholding, payment timing and a final assessment. Unsupported circumstances require the authority’s guidance or a qualified adviser.