X-Rechnung is the official format which is available only in XML and allows electronic invoices to be sent via Peppol *.ZUGFeRD is a hybrid electronic invoice format.
ZUGFeRD has two components: a PDF file and an embedded XML file. Forum elektronische Rechnung Deutschland (FeRD) has developed a standardized data format called ZUGFeRD to enable small and medium-sized businesses and government authorities to benefit from e-invoicing. ZUGFeRD does not replace established EDI and industry standards, but complements them with a simple and cost effective solution for a structured data exchange.
A ZUGFeRD invoice canbe automatically recognized by the invoice recipient, structured data can be transferred directly to the accounting department. The format is a hybrid invoice format that consists of a human-readable PDF and a machine-readable attachment with structured data.