Free, open-source tools for KSeF, Poland's mandatory e-invoicing system. Check an invoice before you send it, see it as a PDF, find the right NBP exchange rate, and learn the rules in plain language. No accounting software needed.
Everything runs in your browser. Your invoice file never leaves it.
| Repository | What it is |
|---|---|
| ksefuj | The ksefuj.to website (validator, PDF preview, NBP rates, guides, blog, docs, FAQ) and @ksefuj/validator: the same FA(3) schema and Ministry of Finance rule checks as an npm package and the ksef-validate CLI |
| skills | Claude skills that generate FA(3) invoice XML and corrective invoices |
| awesome-ksef | A curated list of KSeF tools and resources |
Darmowe narzędzia do KSeF. Sprawdzisz fakturę, zanim ją wyślesz, zobaczysz jej podgląd PDF, znajdziesz kurs NBP do faktury w obcej walucie i przeczytasz poradniki pisane ludzkim językiem. Wszystko działa w przeglądarce, więc plik zostaje na twoim komputerze. Bez zakładania konta i bez limitów.
Free forever, no sign-up, no usage limits. Apache 2.0.