What's the difference between Peppol and UBL?

UBL (Universal Business Language) is the underlying XML standard. Peppol BIS 3.0 is a specific customization of UBL — it defines exactly which fields must be present, which codes can be used, and how parties identify themselves on the Peppol network. Every Peppol BIS invoice is a UBL invoice, but not every UBL invoice is Peppol-compliant.

Does this validate the invoice against Peppol BIS rules?

No. This is a viewer, not a validator. It displays what's in the file but doesn't check whether the file is fully compliant with the Peppol BIS Billing 3.0 business rules.

What file types can I open?

XML files — the standard extension for Peppol and UBL files. Files up to 5 MB are supported.

Is it safe to view invoices here?

Yes. The XML never leaves your browser. The parsing happens entirely client-side in JavaScript — there's no upload, no server processing, no logging.

Do I need a Peppol account to use this?

No. You just need the XML file itself. This tool is independent of the Peppol network.

E-invoice viewer

Open and read an electronic invoice right in your browser, whatever the format. Drop your file below and the viewer detects whether it’s ISDOC, UBL, or Peppol and shows the invoice in a clear, readable layout – amounts, dates, supplier, and line items – without opening your accounting software.

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What is an e-invoice?

An e-invoice is an invoice stored as structured data rather than a picture or a PDF. The data sits in an XML file, so accounting systems can read and process it automatically. The trade-off is that the raw file isn’t readable on its own — open it directly and you see code, not an invoice. This viewer turns it back into something you can read.

Most e-invoices in Europe follow the EN 16931 standard, expressed in one of a few common formats.

Supported formats

This viewer opens:

ISDOC: the Czech national e-invoice standard (.isdoc and .isdocx)
UBL 2.1: the widely used international format for invoices
Peppol BIS Billing 3.0: the UBL-based format used for cross-border and public sector e-invoicing in the EU

Drop any of these and the viewer picks the right one. For format-specific detail and FAQs, use the dedicated pages:

How to open an e-invoice

Select your XML invoice file, or drop it onto the box above.
The viewer detects the format and opens the invoice in a readable layout — supplier, customer, dates, amounts, and line items.
Print it or save it as a PDF using your browser’s print option if you need a copy.

You don’t need to install anything.

How do I know which format my invoice is?

You often don’t need to – the viewer detects it for you. As a rough guide: a file ending in .isdoc or .isdocx is ISDOC; an .xml file from an EU supplier or public body is usually UBL or Peppol. If you’re not sure, just drop it in.

When you might need this

You received an XML invoice and your software doesn’t recognize the format, so you want to read it before importing.
You handle invoices in more than one format and want a single place to open any of them.
You’re testing exports from your accounting or invoicing software and want to confirm the file is correct.
You’re a developer inspecting generated e-invoice files during an integration.

What the viewer shows

Standard invoice information, rendered as a normal-looking document:

Invoice number, issue date, tax point date, due date
Supplier and customer: name, address, registration number, VAT ID, contact details
Line items with quantities, unit prices, and VAT rates
VAT breakdown by rate
Subtotal, VAT total, and total payable
Payment details: IBAN, BIC, and bank account information
Any attachments bundled with the file

Is it safe?

Yes. All parsing happens in your browser. No file or its contents are uploaded, logged, or transmitted. You can open your browser’s developer tools and watch the Network tab while loading a file, nothing carrying the file data leaves your device.

For accountants this matters: invoices hold bank details, customer relationships, and prices that you can’t reasonably hand to a random web service.

Frequently asked questions

Can I open an XML invoice without installing software?

Yes. This viewer runs in your web browser, so there’s nothing to download or install. It works on Windows, Mac, and mobile.

Which formats does this viewer support?

ISDOC, UBL 2.1, and Peppol BIS Billing 3.0. Drop the file and the viewer detects which one it is.

Is my file uploaded anywhere?

No. The file is read directly in your browser and is not uploaded to our servers or stored anywhere. It stays on your device.

What’s the difference between UBL, Peppol, and ISDOC?

UBL is an international invoice format. Peppol BIS Billing is a specific profile of UBL used for cross-border and public sector e-invoicing in the EU. ISDOC is the Czech national standard. All three carry the same kind of invoice data in slightly different structures.

Can I convert an e-invoice to PDF?

You can open the invoice here and then use your browser’s print option to save it as a PDF. That gives you a readable copy you can file or forward.

About this tool

This viewer is built and maintained by Verifical – a document exchange platform for accountants and their business clients, with deep support for the Czech market. ISDOC, Peppol/UBL, and PDF are all first-class formats on our platform.

If you’re an accountant receiving documents from many clients, our main platform handles e-invoice ingestion, archival, and export to your accounting software automatically.

Related tools

ISDOC viewer: the Czech e-invoice format, with ISDOC-specific context and FAQ
UBL invoice viewer: for generic UBL 2.1 files
Peppol invoice viewer: for Peppol BIS Billing files

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