After datly.eu and foldly.eu there is a third evening project: incomly, a German gross-to-net salary calculator at incomly.eu. The idea is the same as with the other two. A tool that many people need regularly exists online almost exclusively with ad banners, cookie walls and questionable accuracy. That can be done better.
What incomly does
The main calculator turns a gross salary into the 2026 net figure, covering everything a real German payslip contains:
- Tax classes 1 to 6, federal state selection (church tax 8 or 9 percent), child allowances
- Statutory or private health insurance, including the additional contribution rate and the automatically calculated employer subsidy under § 257 SGB V
- Faktorverfahren for tax class 4 with the factor from ELStAM
- Company pension (deferred compensation) with the correct tax and social-security effects
- Wage tax allowance and exemptions from pension and unemployment insurance
On top of that there is a dedicated tax class comparison for couples: it calculates the combinations 3/5, 4/4 and 4 with factor side by side and shows which model yields how much net income.
Every result can be shared as a link (the complete input state lives in the URL hash) and saved as a PDF via the print function.
How accurate is it?
Accuracy was the main reason to build this at all. The wage tax is not re-implemented by hand but generated directly from the official calculation specification (PAP) of the German Federal Ministry of Finance: the ministry publishes the logic as XML, a generator translates it into TypeScript. incomly therefore computes bit-for-bit what the tax office computes.
Cross-checking against the official BMF calculator (82,000 euros gross, tax class 1, private health insurance), incomly was 4 euros per year off the official value, caused by rounding details. Two well-known commercial calculators were around 2,000 euros per year off in the same scenario because they handle the private-insurance case incorrectly.
Privacy as architecture, not as a banner
A salary is sensitive data. So incomly is built in a way that the salary is never transmitted in the first place: the site is a static export and the entire calculation runs in your browser. No request carrying your salary, no cookies, no consent banner. The traffic statistics are a self-written anonymous counter without IP storage.
For the record: incomly is a non-binding estimate, not tax advice. The tax office has the final word, and that note sits next to every result.
The stack
If you know the other projects, you can guess: deliberately unspectacular.
- Next.js 15 (App Router) with TypeScript, Tailwind and shadcn/ui, built as a static export
- next-intl for German and English, with more languages prepared
- Hosting on all-inkl webspace in Germany, deployed via rsync over SSH
Next on the list are more specialised calculators (mini-job, working students, severance pay) and, further out, more countries. If you want to try it: incomly.eu. Feedback, especially about deviations from your real payslip, is very welcome via the contact form.
