Valid German e-invoices from one API

Check any XRechnung, ZUGFeRD or Peppol invoice and see every problem in plain English, with the line it is on and how to fix it. Or send us JSON and get a valid invoice back.

Checked with the official rule sets: EN 16931 from CEN, XRechnung 3.0 from KoSIT and Peppol BIS Billing 3.0 from OpenPEPPOL.

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What the API does

Check invoices you receive

Upload XML or a ZUGFeRD / Factur-X PDF. You get a report your code can read: valid or not, which rule failed, on which line, and what to change. German XRechnung messages come with an English explanation.

POST /v1/validate

Create invoices you send

Post plain JSON with the parties, lines and payment details. Totals and VAT are calculated the way the rules check them, and the XRechnung or Peppol file is validated before you receive it.

POST /v1/generate

Show invoices to people

Turn the XML into a readable page in English or German, using KoSIT's official layout, for your users or your support team.

POST /v1/render

Check an invoice

curl https://your-domain/v1/validate \
  -H "X-API-Key: $EINVOICE_KEY" \
  -H "Content-Type: application/xml" \
  --data-binary @invoice.xml

Create an XRechnung from JSON

curl "https://your-domain/v1/generate?format=xrechnung-ubl" \
  -H "X-API-Key: $EINVOICE_KEY" \
  -H "Content-Type: application/json" \
  -d @invoice.json -o RE-2026-0042.xml

Every field and response is described in the interactive API reference. An example request body: invoice-example.json.

Germany's B2B e-invoicing deadlines

1 January 2025
Every business in Germany must be able to receive e-invoices.
1 January 2027
Businesses with more than €800,000 turnover in 2026 must send them. Paper and plain PDF invoices no longer count for their domestic B2B sales.
1 January 2028
All other businesses must send them. Small businesses under § 19 UStG (Kleinunternehmer) and invoices up to €250 stay exempt.

Early-access pricing

Every call counts as one document, whether it checks, creates or displays an invoice. Prices may change before launch.

Plan	Documents a month	Price	Good for
Free	100	€0	Trying it out, small tools
Starter	2,000	€29 a month	An invoicing app with its first customers
Pro	20,000	€79 a month	Software with steady invoice volume

Get early access

Tell us what you are building. You get an API key as soon as your slot opens.