What is an ISDOC file?

ISDOC is the Czech national standard for electronic invoices. It’s an XML file, so the invoice is stored as structured data rather than a picture or a PDF. That lets accounting systems read it automatically, but it also means the raw file isn’t easy to read on its own. This viewer turns it into a normal, readable invoice.

Most Czech accounting and invoicing systems can create ISDOC files, including POHODA, Money, and Helios.

How to open an ISDOC file

• Select your .isdoc or .isdocx file, or drop it onto the box above.
• The invoice opens 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.

ISDOC and ISDOCX: what’s the difference?

Both hold the same invoice data. An .isdoc file is the invoice on its own. An .isdocx file is a package that also includes attachments, such as a PDF copy or supporting documents, bundled with the invoice. This viewer opens both.

• .isdoc — a plain XML file containing the invoice data
• .isdocx — a ZIP archive containing the XML plus any attachments (PDF copies, contracts, etc.)

The viewer opens both. For .isdocx files, drop the archive directly — the viewer extracts the inner XML automatically.

ISDOC versions

The format has gone through several revisions:

• ISDOC 5.x — earlier versions, still encountered in older archives
• ISDOC 6.0.1 — the current stable version, used by most modern software

This viewer reads both. The current ISDOC 6 schema is what almost all production systems output now, so you’re most likely to encounter files using namespace http://isdoc.cz/namespace/2013.

Where ISDOC fits versus Peppol

The Czech Republic, like other EU member states, is gradually adopting Peppol BIS Billing 3.0 for public sector and cross-border e-invoicing under EU mandates. ISDOC remains widely used domestically, particularly between Czech businesses using Czech accounting software. But the long-term direction is mixed: ISDOC for many domestic flows, Peppol for cross-border and public procurement.

If you’re working with both formats, the same viewer handles both — drop in an ISDOC file or a Peppol XML and it detects the format automatically.

When you might need this

• You’re a Czech accountant and a client forwarded you an .isdoc file from a supplier that you want to check before importing
• You’re testing exports from your accounting software and want to confirm the ISDOC file produced is what you expect
• You’re a developer integrating ISDOC import or export into a system and need a quick way to inspect generated files
• You’re working with a Czech vendor from outside the Czech Republic and received an ISDOC invoice that your local tools don’t recognize

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: typically 21%, 12%, and 0% under current Czech rates
• Subtotal, VAT total, and total payable
• Payment details: IBAN, BIC, bank account in Czech format (account number / bank code), and the all-important variable symbol (variabilní symbol) for payment matching
• Any attachments embedded in the .isdocx archive

Czech-specific fields like the variable symbol and the company registration number and VAT ID pair are preserved and labeled clearly.

Is it safe?

Yes. All parsing happens in your browser via JavaScript. No file or contents are uploaded, logged, or transmitted. Open your browser’s developer tools and watch the Network tab while loading a file — you’ll see nothing carrying the file data.

For Czech accountants in particular, this matters: invoices contain bank details, customer relationships, prices, and other commercially sensitive information that you can’t reasonably hand over to a random web service.

Frequently asked questions

Can I open an ISDOC file 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.

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 programs create ISDOC files?

Most Czech and Slovak accounting and invoicing software can export ISDOC, including POHODA, Money, and Helios. The file usually has an .isdoc or .isdocx extension.

Can I convert an ISDOC file 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.

Why can’t I just open an ISDOC file directly?

Because it’s an XML file, opening it directly shows the raw code, not a readable invoice. This viewer formats it the way you’d expect an invoice to look.

Related tools

• Peppol invoice viewer: same tool with Peppol-specific context and FAQ
• UBL invoice viewer: for generic UBL 2.1 files including non-Peppol UBL

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 is a first-class format on our platform, alongside Peppol/UBL and PDF.

If you’re a Czech accountant receiving documents from many clients, our main platform handles ISDOC ingestion, archival, and export to your accounting software automatically — Pohoda, Money S3, and others.