Belastingmate
A Dutch income tax calculator for people with more than one income stream — logs salary, profit and other earnings, then computes box 1 and Zvw the way the Belastingdienst rounds it.
Built for employees, freelancers and side-hustlers in the Netherlands who need to know what they actually owe before the aanslag arrives.
What it does
Log monthly income from three sources — salary, business profit and other earnings — plus deductible costs, and the app calculates box 1 income tax and the Zvw contribution using the current rates, rounded the way the Tax Authority does. Supports the 2025 and 2026 tax years, with interactive charts and CSV/PDF export.
Everything is stored locally: no cloud sync, no account. A one-time €3.99 Plus purchase removes ads and unlocks export.
It’s an indication, not tax advice — box 3, subsidies and personal deductions are out of scope.