Open a ZUGFeRD invoice

You can open a ZUGFeRD invoice in your browser with the Klarbon viewer: drop the PDF and it shows the invoice data from the XML embedded inside, as a readable invoice. It is free and unlimited, needs no account and the file never leaves your device. Viewing does not validate the file; Check does that.

What is inside a ZUGFeRD PDF?

A ZUGFeRD invoice is a PDF that carries a second, machine-readable copy of the invoice as CII XML, attached inside the file (FeRD). People read the PDF page; software reads the XML. ZUGFeRD is technically the same as the French Factur-X, and the current release is ZUGFeRD 2.5.2, paired with Factur-X 1.09.2 (FeRD release notes).

The XML is what counts for e-invoicing. The visible page and the XML should match, but nothing in a PDF reader proves that they do, or even that XML is present. The viewer shows you the XML side. More in what is ZUGFeRD.

How do I open a ZUGFeRD invoice?

Drop the PDF on the viewer or tap to choose it. Klarbon looks for the embedded invoice XML and renders it.

1. Choose or drop the .pdf file. A plain .xml file also works.
2. Klarbon finds the attached XML, detects the ZUGFeRD profile and shows the invoice: parties, numbers and dates, lines, VAT breakdown, totals and payment details.
3. Compare it with the visible PDF if you want to be sure both say the same thing.
4. Print or save a readable copy.

If the PDF contains no invoice XML, the viewer says so. That file is an ordinary PDF invoice, not a ZUGFeRD e-invoice. To create a new hybrid invoice, enter its details yourself in Convert. Automatic PDF reading is not available yet.

Why does the profile matter?

ZUGFeRD comes in profiles with different amounts of data: MINIMUM, BASIC WL, BASIC, EN 16931, EXTENDED and XRECHNUNG. MINIMUM and BASIC WL do not carry all the invoice details EN 16931 requires, so they are not enough for ordinary German B2B e-invoices (BMF FAQ). The viewer shows the declared profile; compare the displayed lines and totals with the original PDF rather than relying on the profile label alone.

Can I read a ZUGFeRD invoice on my phone?

Yes. The viewer works in any modern browser on iPhone, iPad, Android, Windows, macOS and Linux. On an iPhone, pick the PDF from Files or Mail. On Android and desktop Chrome or Edge, you can install Klarbon from the browser and share attachments straight to it.

Is my invoice uploaded?

No. Open runs entirely in your browser: the PDF is read on your device and is not sent anywhere. Check sends the file to Klarbon's servers for validation. In the manual PDF converter, the reference PDF stays on your device and is not uploaded; the details you type are sent to Klarbon to write and validate the file and are not kept once the file is returned. See what happens to your files.

How do I save a readable copy?

Choose Print, then Save as PDF. The copy lays out the structured data clearly and is useful for approval or your Steuerberater. It is not a new ZUGFeRD file, so keep the original PDF with its XML for your records.

Does opening check that the invoice is valid?

No. A ZUGFeRD file can open cleanly and still fail its profile rules, carry wrong totals or sit in a PDF that is not valid PDF/A-3. Check the invoice to test the XML against its profile and EN 16931 and to check the PDF container, with guidance on returned findings.

What next?

• German e-invoicing rules and dates
• Check an e-invoice, free within a daily limit
• Convert a PDF into an e-invoice
• Prices, help and all tools