How we validate the calculations
A salary calculator is only useful if the numbers are right. This page explains exactly how we make sure they are — and what to do if you ever spot a discrepancy.
Why external validation matters
Unit tests assert values we derived ourselves. If we misread the law, the code and the tests would agree with each other — and both would be wrong. To break that circularity, every tax-year configuration is additionally verified against independent calculators maintained by Lithuanian accounting and tax firms.
What we check
For every configured tax year we compute net pay at several gross salaries — the minimum wage (MMA), typical mid-range salaries, and high salaries — with 2nd pillar pension both on and off. We compare not just the final net amount but also the individual components where reference calculators show them: income tax (GPM), social insurance (VSD), health insurance (PSD), and the non-taxable amount (NPD).
Agreement means matching to within €0.01. The remaining cent can differ legitimately because some calculators round each component before subtracting while we round the final result. Anything larger than €0.01 is treated as a bug and investigated — never rationalized away.
The most recent full run
The July 2026 validation run compared 16 scenarios across the 2025 and 2026 tax years against multiple independent Lithuanian calculators. All 16 agreed to within €0.01. The same run settled the 2026 average-salary (VDU) question in favour of the adopted legal act (€2,312.15) and confirmed the single-formula NPD that applies from 2026.
Where the constants come from
Tax rates, brackets, VDU, MMA, and NPD formulas are taken from adopted legal acts and official State Tax Inspectorate (VMI) guidance — for example, the 2026 single NPD formula follows VMI’s 2025-07-03 circular R-2727. When a projection and an adopted act disagree, the adopted act wins.
Automated gates on every change
Every code change must pass type checks, linting, the full unit suite (including the cross-validated golden values), a production build, and post-build smoke checks before it can ship. A tax-year constant cannot change silently.
Limitations
This is a universal calculator. Individual circumstances — an increased NPD due to disability, multiple employers, specific collective agreements — can change the result. For a binding answer about your own salary, talk to your employer or an accountant.