Validate XRechnung / UBL files against the XSD

E-invoices such as XRechnung (UBL or CII syntax) are validated in two layers:

1. XML Schema (XSD): is the file well-formed, are the elements in the right place, are dates, amounts and codes of the right type? — This is what this site checks.
2. Schematron business rules (EN 16931 and the XRechnung CIUS): totals add up, mandatory business terms are present, codes fit together. — This needs a Schematron validator, for example the official KoSIT validator.

A file that fails the first layer never reaches the second, so the XSD check is a quick first step when an invoice is rejected.

How

1. Load the invoice XML.
2. Load the schema: for UBL, the UBL-Invoice-2.1.xsd with its common folder as a .zip; for CII, the CrossIndustryInvoice schema bundle.
3. Read the errors in the list or the Excel report; each links to an explanation.

Typical XSD-level problems: dates as 19.10.2026 instead of 2026-10-19 (invalid value), elements in the wrong order after manual edits (element not expected), and amounts with too many decimals (too many digits).

Validate a file