PUB vs PDF: What's the Difference?

If you're Googling "PUB vs PDF," you probably received a .pub file and have no idea what to do with it. Or maybe you're trying to figure out why your .pub files won't open on your new computer.

Let's clear this up. These are two completely different things.

What's a .pub file?

A .pub file is a Microsoft Publisher document. Publisher is (was) a desktop publishing program for creating flyers, newsletters, brochures, and other print materials. It's been around since 1991.

The .pub format is proprietary and locked to Publisher. Microsoft never published how the format works. Almost no other software can open it properly. Not Word, not Google Docs, not Preview on Mac, not Adobe anything.

If you have Publisher installed on a Windows PC, .pub files open fine. If you don't, they're essentially unusable without converting them first.

Important context: Microsoft is discontinuing Publisher in October 2026. After that date, even fewer people will be able to open .pub files.

What's a PDF?

A PDF (Portable Document Format) is a universal document format created by Adobe in 1993. The important word is "portable." A PDF looks the same on every device, every operating system, every screen.

PDFs can be opened by practically everything. Your browser can open them. Preview on Mac opens them. Every phone opens them. Adobe Reader opens them. Google Drive opens them.

The format specification is published and open. Anyone can build software that reads PDFs. That's why support is everywhere.

The main differences

Compatibility. PDFs open on anything. .pub files only open in Microsoft Publisher (Windows only) or with specialized conversion tools.

Editability. .pub files are fully editable in Publisher. You can move text boxes, swap images, change layouts. PDFs are designed to be finished documents. You can annotate them, but restructuring the layout requires specialized software.

Portability. You can email a PDF to anyone and they'll be able to open it. Email a .pub file and most recipients will have no idea what to do with it.

Longevity. PDFs will be readable decades from now. The format is an open standard (ISO 32000). .pub files are tied to software that's being discontinued in 2026. Their long-term accessibility is uncertain.

File size. .pub files tend to be larger because they store editable layout data, embedded fonts, and high-resolution images in their original form. PDFs can be compressed significantly. A 15 MB .pub file might become a 3 MB PDF.

PUB is not the same as EPUB

Quick clarification because this causes confusion: .pub (Microsoft Publisher) and .epub (electronic publication / ebook format) are completely unrelated formats with unfortunately similar names.

If you're looking for information about ebook files, you want EPUB. That's a different format used by Kindle, Apple Books, Kobo, and other ebook readers.

This article is about Microsoft Publisher's .pub format.

When to use each format

Use PDF when:

  • Sharing documents with anyone (they can always open it)
  • Archiving finished documents
  • Printing (PDFs preserve exact layout)
  • Emailing files to people outside your organization
  • Long-term document storage

Use .pub when:

  • You're actively editing a document in Publisher (while Publisher still exists)
  • You need the source file for future revisions
  • You're working with someone else who has Publisher

In practice, this decision is getting simpler. With Publisher going away, .pub files are becoming purely a legacy format. The question isn't "should I use .pub or PDF?" It's "how do I convert my old .pub files to PDF?"

How to convert .pub to PDF

Three options, simplest first:

Online converter (fastest, no installation)

PubConvert converts .pub files to PDF right in your browser. Here's the whole process:

  1. Go to pubconvert.com
  2. Drop your .pub file onto the page
  3. Pick PDF as your output format (or Word, SVG, HTML, or LibreOffice Draw if you need something else)
  4. Click Convert
  5. Download your file

No signup, no installation, works on any device. The preview is free. And if you've got more than one file, PubConvert is the only online converter that handles up to 20 at once in batch mode. Unlimited conversions are $49 one-time.

LibreOffice (free, offline)

Download LibreOffice and open your .pub file with LibreOffice Draw. Then export to PDF. Free, works on Windows/Mac/Linux, and you can edit the file before exporting. The tradeoff is that you need to install software, and complex Publisher layouts don't always survive the conversion perfectly.

Publisher itself

If you still have Publisher, File > Export > PDF. This gives the most accurate conversion since it's using the original software. But Publisher is Windows-only and going away in October 2026, so this option has an expiration date.

Can you convert PDF back to .pub?

No. There's no reliable way to convert a PDF back to an editable .pub file.

If you need an editable version of a .pub file, convert it to LibreOffice Draw format (.odg) instead of PDF. LibreOffice Draw is free and lets you edit the converted file. It's the closest thing to having an editable Publisher file without Publisher.

On PubConvert, just pick "Editable Layout" in the format options instead of PDF. Same drag-and-drop process, same batch support.

So what should you do?

PDF is the universal format. .pub is a proprietary format tied to dying software.

If you have .pub files, convert them to PDF for archival and sharing. If you need to keep editing them, convert to LibreOffice Draw format instead. Either way, the clock is ticking.

The fastest way to find out what your converted files will look like: drop a .pub file onto pubconvert.com right now. It takes 10 seconds, no signup. If you've got a whole folder of .pub files, switch to batch mode and convert up to 20 at a time.

Need to convert .pub to PDF? PubConvert works in your browser. Drop your file in, get a PDF out. Batch convert up to 20 files at once (2GB total). $49 one-time for unlimited conversions. Preview your file free first.