Our Purpose & The Meaning of "Rompslomp"
In the Dutch language, the word "rompslomp" denotes the tedious red tape, bureaucratic paperwork, and administrative friction that every entrepreneur faces when starting out. Between calculating quarterly VAT returns, formatting compliant invoices, keeping mileage logs, and working out billable hourly rates, administrative red tape often consumes hours that could otherwise be spent delivering valuable client work.
Rompslomp.net was built to strip that red tape away. We provide a comprehensive, 30-tool catalog of free financial and bookkeeping calculators that run instantly in your browser without requiring an account, subscription, or disclosure of sensitive financial data.
Trademark & Independence Disclosure
Rompslomp.net is an independent, non-commercial educational and utility project. Rompslomp.net is NOT affiliated with, endorsed by, authorized by, or in any way associated with Rompslomp.nl or Rompslomp B.V. All brand references and trademarks belong exclusively to their respective owners. We do not provide proprietary cloud accounting software; rather, we provide free client-side math calculators and invoice generation templates to assist the European freelance community.
Our Core Architectural Principles
1. 100% Client-Side Privacy
Your finances are your business. Every single calculation, invoice preview, and number runs locally inside your browser's JavaScript sandbox. No client details, rates, or totals are ever saved on remote servers.
2. Integer Precision Math
Computers struggle with binary floating-point decimal math (e.g. 0.1 + 0.2 = 0.30000000000000004). We use integer-cents multiplication to guarantee zero rounding errors on invoices.
3. Belastingdienst Aligned
Our tax rules reflect the official Dutch Tax Administration standards, including the 21% standard and 9% reduced BTW rates, the €0.23/km mileage deduction, and statutory B2B invoicing rules.
4. Zero Barriers to Access
No logins, no cookies required, no email capture walls, and no intrusive paywalls. You arrive, calculate, print or export your invoice, and get back to business.
Editorial Standards & Quality Guarantee
Every guide, formula, and tool published on Rompslomp.net is verified against authoritative government publications, such as Rijksoverheid and the Belastingdienst. When statutory rates change (such as annual updates to mileage allowances or statutory commercial interest rates), our engineering team updates the formulas promptly with clear version notes.
Have questions, feedback, or a suggestion for a new calculation utility? Please visit our Contact Us page.