xrechnung.dev checks German e-invoices in XRechnung (XML, UBL or CII) and ZUGFeRD/Factur-X (PDF) format with the official KoSIT validator (version 1.6.3, XRechnung 3.0.2). Upload a file in the browser and see at once whether it is valid, which rule failed, and what the invoice says: seller, buyer, line items, totals, IBAN.
Every error code is explained in plain German, with the cause and the fix. If an invoice you received is invalid, the tool gives you a ready-made text to request a corrected invoice from the sender.
Developers get a REST API to validate, parse and generate XRechnung XML and ZUGFeRD PDF. Every generated file is validated before it is delivered. There is also a WooCommerce plugin, a Chrome extension, a Python package and a GitHub Action.
10 documents a month are free, with no sign-up and no credit card. Paid plans start at €19 net per month and can be cancelled monthly. Servers in Frankfurt, Germany; files are discarded after the check. xrechnung.dev is independent and not affiliated with KoSIT.
