Formats

xTool supports several e-invoicing formats. Each document has one format; it determines validation rules and available conversions and transforms. See Document model, Format models (field reference), Validate and convert, and API Reference for Format endpoints.

Each format has a unique format code; a format model (in essence, the file as read by xTool), which can be represented as JSON; and file content in its native form — XML, PDF, IDoc or other types depending on the format.

flowchart TB
    CODE["Unique format code"]
    MODEL["Format model (JSON)"]
    CONTENT["File content: XML, PDF"]
    CODE --- MODEL
    MODEL <-->|transformation| CONTENT

Format table

Format code	Document type	Representation	Peppol
xtool.invoice.1_0, xtool.credit_note.1_0	Invoice, Credit note	Internal model	No
xrechnung.invoice.3_0.xml_ubl, .xml_ubl.extension, .xml_cii	Invoice	XML (UBL, CII)	Yes (UBL)
xrechnung.credit_note.3_0.xml_ubl	Credit note	XML (UBL)	Yes
peppol_bis_billing.invoice.3_0.xml_ubl, .xml_cii	Invoice	XML (UBL, CII)	Yes
peppol_bis_billing.credit_note.3_0.xml_ubl	Credit note	XML (UBL)	Yes
peppol_bis_self_billing.invoice.3_0.xml_ubl, .credit_note.3_0.xml_ubl	Invoice, Credit note	XML (UBL)	Yes
factur_x_zugferd.invoice.2_4.pdf_xml.en16931, .pdf_xml.xrechnung	Invoice	PDF + embedded XML	Yes (XRechnung)
sap.invoice.idoc	Invoice	IDoc	No

How format is used

Documents — When you create or upload a document, you choose a format (or it is detected from XML). Validation and conversion use this format.
API — The Format endpoints (validate model/XML, transform model↔XML, model→PDF, XML→model, XML→PDF, convert, detect XML) take or return a format code. See Validate and convert.

Understanding field meanings (semantics)

To understand what each field means (invoice number, issue date, seller, buyer, line items, totals, etc.) and how to fill the form or API request body, see Format models (field reference). For a detailed section-by-section and field-by-field reference with JSON/XML examples, see Invoice model understanding. For full and minimal examples, see Base invoice model example and Minimal invoice model.

Choosing a format

Peppol — Use a Peppol-supported format (e.g. Peppol BIS Billing, XRechnung UBL) as required by your network or country. See Peppol and Send by Peppol.
Public sector (e.g. Germany) — XRechnung and ZUGFeRD are commonly required. Check local regulations for the mandatory format.

Custom formats — we can implement a format to your requirements on request. Contact support.

!!! tip "Local requirements" Check your country or sector requirements for the mandatory e-invoicing format before choosing. Or contact us via support for advice.