Open UDF Files Online – UDF Viewer

How do you open a UDF file? Four ways

The only official way to open a UDF file is the UYAP Document Editor, but it is not always the most practical. Which way suits you depends on what you want to do with the document:

• In the browser (this page): nothing to install, works on any device. Enough for reading, searching, printing and converting to PDF.
• UYAP Document Editor: required if you need to edit the document, sign it with an e-signature or submit it to UYAP. It is available for Windows, Mac and Pardus (a Turkish Linux distribution).
• On a phone: save the file you received on WhatsApp or by e-mail, then open it from this page. The official mobile app exists too, but it only displays documents.
• On a Mac: open it in Safari or Chrome and avoid the editor's Java and printing problems.

What the viewer offers

The viewer lays the document out into pages using the page settings stored in the UDF: margins, header and footer, page numbers, tables and images all appear in place. Some tools make reading easier:

• Page view, and a page-free reading view that is comfortable on a phone.
• Search inside the text, with correct handling of Turkish upper and lower case (İ/i, I/ı).
• Zoom, fit to page, pinch to zoom and full screen.
• Light, dark and sepia themes.
• Printing, and download as PDF, Word, plain text or XML.
• An overview tab with page setup, paragraph and table counts and the styles used.
• XML and plain-text tabs, to see the raw content of the document and copy its text.

E-signature information and the verification code

The UYAP Document Editor shows a ribbon icon on signed documents. This viewer also shows whether the document carries an e-signature and, if so, lists the name of the signer, the time of signing and the authority that issued the certificate. If a panel of judges or an expert committee signed, every signature is listed. The national ID number in the certificate is not shown.

We also check whether the content covered by the signature matches the content in the file. If it does not match, the document has been changed after it was signed, and you should not upload such a file to UYAP. This check is not a verification: the validity and revocation status of the certificate are not checked. If the document stores a UYAP document verification code, the viewer shows it, and you can use it to check the original through UYAP's own verification service.

What if it will not open?

The viewer recognises a file by its content, not by its name. UDF files that WhatsApp has renamed "Document.udf.zip", or whose extension was lost in an e-mail, therefore usually open without trouble, and you can download a copy with the corrected .udf extension if you wish. If a file is truly damaged, or is not a UDF at all (for example an EYP package, a TIFF or a real RAR archive), the tool says so in a clear message. A UDF is technically a ZIP archive, which is why it can appear as one; see What is a UDF file?.

Is opening a file online safe?

"Online" often means the file travels to a server. Here it does not. The viewer is downloaded to your browser together with the page, and your file is opened in your browser's memory. When you close the tab the document is gone from memory; nothing is stored anywhere. For decisions, notifications and records that contain personal data, this is very different from uploading the file to a company's server. To check it yourself: How can you be sure?

Which way for which device?

The answer to "which program opens a UDF file?" depends on your device:

• Windows: this page for reading; the Windows version of the UYAP Document Editor for editing and signing.
• Mac: this page in Safari or Chrome for reading and printing; the Mac version of the editor for signing (there are separate packages for Intel and Apple silicon).
• Linux and Pardus: this page in Firefox or Chrome; a Pardus/Debian package of the editor is available as well.
• iPhone and iPad: this page in Safari.
• Android: this page in Chrome. If you add the site to your home screen, you can send a file from WhatsApp to it with the Share menu.

After reading: convert and copy

The viewer is not only for reading. Download the document as a PDF to send it to a client, or as Word to work on it. If you want to quote a paragraph, the text tab shows the plain text of the document so you can copy it. For technical inspection, the XML tab shows the raw content and the overview tab shows the page setup and the styles in use. Remember that a converted file is a copy without an e-signature: see UDF to PDF and UDF to Word.