Upload a UBL or CII invoice — or a Factur-X / ZUGFeRD PDF, or a ZIP of up to 200 invoices — and get the rule that failed, what it means in plain English, and how to fix it. Free, no account, nothing stored.
No invoice to hand? Try a sample with a VAT rounding error or the same invoice against Peppol rules, or against XRechnung (Germany). Or grab a sample invoice to test your own code with.
Every EN 16931 and Peppol BIS rule has its own reference page with the cause and the fix.
Factur-X and ZUGFeRD PDFs are unpacked and the XML checked — plus the container itself: /AF, /AFRelationship and the XMP profile declaration, which almost nothing else looks at.
An invoice can be valid EN 16931 and still bounce off Peppol or XRechnung. The Peppol check adds the national rules for DE, DK, GR, IS, IT, NL, NO and SE automatically, from the seller's country.
Passes 1,142 of 1,142 assertions in CEN's own EN 16931 test suite — the same corpus the standard is validated with.
Country-by-country mandate deadlines — Belgium, Poland, France, Germany, Slovenia and the rest.