PDF Version Checker

Runs in browser PDF Analysis & Repair

Shows the header version, a /Version override in the catalog, the effective version, which readers support it, and features such as object streams, AES-256 encryption, transparency or JPEG 2000 that set a minimum version.

Privacy: Processed locally in your browser. Your file is not uploaded.

What is inside a PDF file, and what does repairing one do?

A PDF is a header naming its version, a body of numbered objects (pages, fonts, images, streams), a cross-reference table that records where each object starts, and a trailer pointing at the catalogue and the metadata. Metadata lives in the Info dictionary (title, author, dates, producer) and, since PDF 1.4, in an XMP stream; fonts are embedded whole, subsetted or only referenced by name. A viewer that cannot find an object walks the file to rebuild the cross-reference table — repair does the same and writes the rebuilt table, which fixes most "damaged file" errors without touching the pages.

How to use PDF Version Checker

  1. Drop one or more PDFs.
  2. Click "Check version".
  3. Read the effective version and the features that raise it.

PDF Version Checker features

  • Header version and catalog /Version override
  • Effective version and reader support
  • Detects object streams, AES-256/128/RC4 encryption, transparency, JPEG 2000
  • Several files with a comparison table
  • Explains what each feature requires
  • Local processing

PDF Version Checker example

Is this file safe for an old reader?

Input:

archive.pdf

Output:

Header 1.4 · catalog — · effective 1.4 · features: none → Acrobat 5 (2001) and later

Frequently asked questions about PDF Version Checker

Where is the version stored?

In the first line of the file (%PDF-1.7) and, optionally, in the catalog’s /Version key, which overrides the header when it is higher. The effective version is the greater of the two.

Can I change the version?

Files saved by this site’s tools are written as PDF 1.7 (or 2.0 when AES-256 encryption is used). The version is a declaration, not a conversion: a "1.4" file that uses AES-256 will still need a modern reader.

Which version should I target for compatibility?

PDF 1.4–1.7 opens everywhere. PDF 2.0 features (AES-256, UTF-8 strings) need readers from about 2017 onwards.

Is my PDF uploaded to a server?

No. The file is opened and processed by your browser with WebAssembly and JavaScript; nothing is sent to Mutqan Soft or anyone else. Close the tab and the file is gone. Downloading the result needs a free account — no subscription, no payment.

Can I use it on a password-protected PDF?

Yes, if you know the password: the file list asks for it once and every operation then works on the decrypted pages. The output is saved without a password unless you protect it again.

Technical notes

The header is read from the first kilobyte, the /Version name from the catalog; feature detection scans the head and tail for xref/object streams and JPX images, reads the /Encrypt dictionary for the cipher and looks for soft masks and constant alpha as transparency markers.

References