E-Invoicing Knowledge Base
10 guidesWhat is Peppol?
Peppol is a secure international network that enables businesses and governments to exchange electronic documents like invoices, orders, and catalogs.
Read guideStandards & Networks
Peppol
Peppol is a secure international network that enables businesses and governments to exchange electronic documents like invoices, orders, and catalogs.
EN 16931
EN 16931 is the European standard that defines the semantic data model for electronic invoices, ensuring interoperability across all EU member states.
E-Invoice Formats
XRechnung
XRechnung is Germany's official e-invoice format for public sector transactions, implementing the European standard EN 16931 with additional German-specific business rules.
ZUGFeRD
ZUGFeRD is a hybrid e-invoice format that embeds structured XML data inside a PDF/A-3 file, allowing invoices to be both human-readable and machine-processable.
Factur-X
Factur-X is a hybrid e-invoice format that embeds structured XML data inside a PDF/A-3 file, identical to ZUGFeRD but marketed under a Franco-German partnership.
UBL
UBL (Universal Business Language) is an open XML standard for business documents including invoices, developed by OASIS and widely used for e-invoicing via the Peppol network.
CII
CII (Cross-Industry Invoice) is a UN/CEFACT XML standard for electronic invoices, used as the embedded format in ZUGFeRD and Factur-X hybrid invoices.
Tools & Features
Quick Start: Fix E-Invoice Errors
Invoice Navigator's Fixer tool automatically corrects technical errors in your e-invoices, making them compliant in seconds.
What We Fix Automatically
Auto-fix errors are technical issues we can correct without any input from you—just upload and download.
an Evidence Pack
An Evidence Pack is a comprehensive audit trail document proving what was validated, what was fixed, and that your invoice is compliant.
Format Comparisons
XRechnung vs ZUGFeRD
XRechnung is a pure XML format required for German government invoicing, while ZUGFeRD is a hybrid format combining PDF and XML that works for both business and government transactions. Both comply with the European standard EN 16931, but they serve different purposes.
Peppol vs Factur-X
Peppol is a document exchange network, while Factur-X is a file format. They solve different problems and can work together—you can convert a Factur-X invoice to Peppol BIS format and send it via the Peppol network.
UBL vs CII
UBL (Universal Business Language) and CII (Cross-Industry Invoice) are two XML syntaxes for expressing EN 16931 invoices. Both carry the same business information—the difference is technical structure. Your choice usually depends on which formats and networks you need to support.
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