Who runs this site, where the numbers come from, and what they are and are not good for.
tax-calculator.nl is a set of calculators for working out what Dutch tax rules mean for your own situation: gross-to-net salary, the 30% ruling, holiday allowance, motor vehicle tax, mortgage interest deduction, and an annual tax return estimate. Alongside them is a small library of guides explaining the rules the calculators apply.
It exists because the official figures are published as tables and legislation, not as an answer to the question most people actually have, which is what lands in their bank account each month. Every calculator is free to use without an account. Paid plans add saved profiles, scenario comparison, and exports.
The site is built and maintained by Ekim Basoglu, an independent software developer based in Serbia. It is a one-person project, not a company, not a tax advisory practice, and not affiliated with the Belastingdienst or any other government body.
The relevant expertise here is engineering, not tax law: the work is reading the published rules carefully and implementing them exactly. Where a rule is ambiguous, the guides say so rather than picking a number and presenting it as settled. Being outside the Netherlands is the reason every figure on this site is traced back to a named Dutch source rather than to local knowledge, and why the sources are listed below instead of left implicit.
Rates, brackets, credit amounts, and thresholds come from the Belastingdienst and other primary Dutch sources. Nothing is copied from other calculators.
Each calculator page states the tax year it covers and the date its figures were last checked against the source. When the rules change, the calculators are updated, typically ahead of the new calendar year, and previous years stay available so you can reproduce an older result.
Calculations run in your browser. Nothing you type is sent to a server unless you are signed in and deliberately save a profile. There is no model or estimate layer in between: the calculators implement the published formulas directly, which is why a result can be checked line by line against your payslip.
Results are still estimates. They cannot see your full circumstances, and payroll software makes rounding and timing choices that shift the final figure slightly. Treat the output as a well-sourced approximation for planning, not as a filing document or as tax advice. For a binding answer, consult a qualified Dutch tax adviser or the Belastingdienst directly.
If a result looks wrong, it might be. The calculator dashboards have a report button that sends your current inputs and the computed result so the calculation can be reviewed against the source rules.
For anything else, including questions about the guides, email contact@tax-calculator.nl.