Keep opening your Publisher files.
OpenPub opens Microsoft Publisher .pub files on Windows — without Publisher,
without LibreOffice, without anything else installed.
.exe, about 63 MB. No installer, no account.
Microsoft retires Publisher in October 2026. After that, Publisher stops being available and supported — but the files people made with it don't go anywhere. OpenPub exists so those files stay readable.
What it does
- Opens
.pubfiles directly — no conversion step, no upload to a website, no other software required. - Works offline. Your documents never leave your machine.
- Treats every file as potentially hostile. Publisher's format is undocumented and parsing untrusted binary files is where things go wrong, so the parsing happens in a locked-down sandbox.
How it reads a file safely
Every .pub file is parsed by a small, separate helper program that runs inside a
Windows sandbox. That helper cannot open other files, use the network, start programs, or touch
the registry. It receives the file and returns plain structured data, which OpenPub then checks
and bounds before displaying anything.
This matters because opening a document should never be a way onto your computer. A malformed or
deliberately malicious .pub file has nothing to reach from inside that sandbox.
Requirements
- Operating system
- Windows 10 version 1903 (May 2019) or newer, 64-bit
- Download size
- Approximately 63 MB — a single
OpenPub.exe - Installation
- None. Save the file and run it.
- Price
- Free
The Windows 10 1903 requirement is deliberate: OpenPub uses the text-handling library already built into Windows rather than bundling its own copy, which keeps about 31 MB out of every download. On an older version it says so plainly rather than failing in a confusing way.
Open source components
OpenPub's file parser is built on libmspub, an open-source library for reading Publisher files. The source for the components that require publication, along with full licence notices, is included with every release.