Free Tool Desk

KSeF FA(3) XML Viewer

Open a Polish KSeF structured invoice (FA(3)) and read it as a table. Checks the XML against the official schema. Runs in your browser.

Free to use No sign-up required Nothing is uploaded

W Krajowym Systemie e-Faktur faktura to plik XML, a to, co widzisz jako PDF lub wydruk, jest tylko jej wizualizacją. Jeśli dostałeś plik XML i chcesz wiedzieć, co w nim jest, ten podgląd pokaże strony, pozycje, podatek i płatność w czytelnej tabeli. (In English: in KSeF the invoice is the XML file; anything you see as a PDF or printout is a visualisation.)

The viewer reads FA(3), the logical structure that applies from 1 February 2026, and checks the file against the official schema. What it shows is a visual representation made in your browser, not the invoice issued in KSeF.

Loading the tool…

Overview

About KSeF FA(3) XML Viewer

What FA(3) is. FA(3) is the structure of the Polish structured invoice as published by the Ministry of Finance in the Central Repository of Electronic Document Templates; it replaces FA(2) from 1 February 2026. A file is recognised as FA(3) by its root element Faktura in the namespace http://crd.gov.pl/wzor/2025/06/25/13775/, together with the form code FA (3) and schema version 1-0E in the header. If a file is in another namespace or declares a different form code, the tool says so instead of showing it as FA(3).

What it shows. Invoice type (standard, correcting, advance and so on), number, issue date and place, date of sale or delivery, currency, seller (Podmiot1) and buyer (Podmiot2) with NIP and address, every line with name, unit, quantity, net price, net value and VAT rate, the totals per VAT rate group, the amount due (P_15), the forms of payment, due date and bank account, and notes. The raw XML and a download are underneath.

Schema check. The XML is validated against the official FA(3) schema (schemat.xsd with its data-type schemas) using the libxml2 engine compiled to WebAssembly, in your browser. A pass means the structure matches the schema; it does not mean the invoice is correct in tax terms, and KSeF applies further rules when an invoice is submitted.

Visualisation, not the invoice. The page you see, and anything you print from it, has no KSeF number, no acknowledgement (UPO) and no legal status. The Ministry of Finance applications (KSeF taxpayer application, mobile app) are the places that produce the official visualisation.

Compatibility

Supported Formats

XML files up to 5 MB in the FA(3) structure (schema version 1-0E). Files in the older FA(2) structure are recognised as another form and are not displayed as FA(3). PDFs and non-XML files are not accepted here; use the E-Invoice Format Detector if you are not sure what a file is.

Guide

How to Use KSeF FA(3) XML Viewer

  1. Drag in the FA(3) XML file (or choose it).
  2. Check the detection card: it should say KSeF structured invoice FA(3) and show the schema version.
  3. Read the invoice table and the VAT rate groups; compare the amount due with the XML.
  4. Look at the schema-validation result under the table. If it lists problems, the line number points at the XML.
  5. Download the XML if you need the original file.

Highlights

Features

  • Recognises FA(3) by its signals Root element, official namespace, form code and schema version; anything else is reported as not FA(3).
  • Official schema check Validates the XML against the Ministry of Finance schema, in your browser, with the problem lines listed.
  • Polish fields in plain English Invoice type, VAT rate groups, forms of payment and bank account labelled so you can read them without the schema documentation.
  • Clear about what it is not Says on the page that the view is a visualisation, not the KSeF invoice.

Applications

Use Cases

  • Reading an invoice file received from a supplier or accountant without logging in anywhere
  • Checking an XML your invoicing software generated before it is sent to KSeF
  • Finding which field of an XML causes a schema error
  • Explaining an invoice to a colleague who does not read XML
  • Telling an FA(3) file apart from an older FA(2) file

Good to Know

Limitations

The view does not reproduce the official Ministry of Finance visualisation and does not display every FA(3) element. Attachments (the Zalacznik block), correction details and rarely used sections are visible in the XML but not all laid out in the table. VAT rate groups are shown as the schema defines them (P_13_x and P_14_x fields).

Schema validity is structure only. The tool does not know whether the NIP is registered, whether the invoice number series is correct, whether VAT has been calculated correctly, or whether KSeF would accept the invoice. It does not contact KSeF.

This tool runs entirely in your browser — your file is never uploaded to our servers. See our Privacy Policy for full details.

Support

Frequently Asked Questions

Is what I see here the invoice from KSeF?

No. In KSeF the invoice is the structured XML. This page is a visual representation generated in your browser. It has no KSeF number or confirmation and no legal status.

Which FA(3) schema does it use?

The official schemat.xsd published on crd.gov.pl for namespace http://crd.gov.pl/wzor/2025/06/25/13775/, schema version 1-0E, together with the three data-type schemas it imports. They are served from this site, not fetched from another host.

Since when is FA(3) used?

The Ministry of Finance published FA(3) in June 2025 and it is the applicable structure from 1 February 2026, replacing FA(2).

The schema check passes but KSeF rejects my invoice. Why?

A schema describes structure. KSeF also checks business and identification rules when an invoice is submitted. A pass here means the XML is shaped correctly, nothing more.

Is my invoice uploaded for the schema check?

No. The check runs in a worker in your browser; the schema files come from this site and the invoice text never leaves the page.

Why are some fields in Polish?

The tool shows English labels for the fields it displays and keeps your values as they are written in the XML (names, addresses, descriptions). The schema error messages come from the validation engine and may refer to Polish element names.

Keep Going

Related Tools