Psi is a free instant messaging client for the XMPP protocol which uses the Qt toolkit. It runs on Linux (and other Unix-like operating systems), Windows, macOS and OS/2 (including eComStation and ArcaOS).
User interface of program is very flexible in customization. For example, there are "multi windows" and "all in one" modes, support of different iconsets and themes.
Ready-to-install deb and RPM packages are available for many Linux distributions. Successful ports of Psi were reported for Haiku, FreeBSD and Sun Solaris operating systems.
Due to Psi's free/open-source nature, several forks have appeared, which occasionally contain features that may appear in future official Psi versions.
'Psi' is the twenty-third letter of the Greek alphabet (Ψ), which is used as the software's logo.
The goal of the Psi project is to create a powerful and easy-to-use XMPP client that tries to strictly adhere to the XMPP drafts and XMPP XEPs. This means that in most cases, Psi will not implement a feature unless there is an accepted standard for it in the XMPP community.
From the Wikipedia article “Psi (instant messaging client)”, CC BY-SA 4.0
What is Psi?
Psi by the Psi team is open-source Windows software in the chat & messaging category. It ranks 21st by popularity among chat & messaging in this catalogue. The first release dates back to 2001. It is written in C++. Besides Windows, it is available for Unix-like operating system and macOS. Its interface is available in 35 languages.
Installation and requirements
The publisher provides EXE (NSIS) installers for 64-bit Windows. The main installer is 84.0 MB. Installation asks for administrator rights. A silent install is possible with the installer’s documented switches.
Popularity and file types
The Chocolatey package has been downloaded 3,187 times. The source code on GitHub (psi-im/psi) has 444 stars. Wikipedia has an article about it in 17 of our languages. Similar programs include Signal, Discord and Telegram Desktop.
Project description on GitHub: “XMPP client”
Pros / Cons
Pros
- Open source: the code can be inspected and built by anyone
- Documented silent install
- Also runs on Unix-like operating system and macOS
- Mature project (since 2001)
- Interface in 35 languages
Cons
- No native ARM64 build
- Installation needs administrator rights
- No update for more than a year
In short: Psi is an open-source chat & messaging tool for 64-bit PCs. Updates have slowed down. Administrators can deploy it unattended.
Screenshots
Is Psi safe to download?
- The file is served by sourceforge.net; check that it is the publisher’s official mirror
- The download link uses HTTPS
- A SHA256 hash is published, so you can verify the file:
BAEBF61259D746AD6B9ED2B8E77FB34ECBE9892F5C58C424B25DB1AD6F6543A2· Open the VirusTotal report for this hash - The link answered when we last checked it (October 22, 2026)
- The source code is public
- ExeAtlas does not host, wrap or modify installers
Related guide: How to check a file’s SHA256 hash on Windows
Security practices (OpenSSF Scorecard)
Automated checks of the psi-im/psi repository on GitHub by the Open Source Security Foundation, last run on October 19, 2026.
- Actively maintained10
- No dangerous workflows10
- No binaries in the repository10
- Licence declared9
- Branch protection1
- Code review0
- OpenSSF Best Practices badge0
- Restricted token permissions0
- Security policy0
- Pinned dependencies0
- Fuzzing0
- Signed releases0
- Static code analysis0
The score rates how the project is developed and released, not whether the program is safe to install. scorecard.dev
Recent versions
All 1 versions ›| Version | Date | Size | Files |
|---|---|---|---|
| 1.3Latest | September 24, 2017 | 84.0 MB | 64-bit EXE (NSIS) |
Install from the command line
Silent install ›winget install --id Psi.Psi -echoco install psi.install -ydownload /SRelated guide: How to use winget: install and update apps
Information
- Publisher
- the Psi team
- Category
- Chat & messaging
- Licence
- GPL-2.0
- Price
- Free
- Source code
- github.com/psi-im/psi
- Written in
- C++
- Interface languages
- English, Russian, Ukrainian, Czech, Italian, and German +29 more
- Requires
- Windows 11 / 10
- Architecture
- 64-bit
- Installer
- EXE (NSIS)
- Other platforms
- Unix-like operating system, macOS
- Version
- 1.3
- Released
- September 24, 2017
- First release
- 2001
- Added to the catalogue
- April 14, 2025
- Versions listed
- 1
- Chocolatey downloads
- 3,187
- GitHub stars
- 444
- GitHub forks
- 129
- Website
- psi-im.org
- winget ID
- Psi.Psi
- Chocolatey package
- psi.install
Ratings and reviews
No reviews yet. Be the first to rate it.
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Frequently asked questions
Is Psi free?
Yes. Psi is open-source software under the GPL-2.0 licence.
Is Psi safe to download?
The download comes from sourceforge.net; ExeAtlas does not host or change the file. Compare its SHA256 hash with the one shown here, or open the VirusTotal report for that hash.
How do I install Psi with winget?
Open PowerShell or Windows Terminal and run the winget command shown on this page. winget downloads the official installer and checks its SHA256 hash before running it.
Can Psi be installed silently?
Yes. The silent install page lists the exact command for each installer.
Does Psi run on ARM (Windows on Arm)?
There is no ARM64 build; Windows 11 on Arm can run the 64-bit version through emulation.
What are alternatives to Psi?
Signal, Discord, Telegram Desktop, Slack and Viber. The alternatives page compares them.
