This is a utility with a graphical user interface and a command line interface that can be used to view and extract the contents of an MSI file.
Publisher’s description
What is lessmsi?
lessmsi is an open-source archiver program for Windows from Scott Willeke. It ranks 9th by popularity among archivers in this catalogue. It is written in C#.
Installation and requirements
Official installers exist for Any CPU as Portable. It runs without installation (portable).
Updates and version history
The current version is 2.12.9, released on April 2, 2026. 34 versions are listed since February 28, 2025, each with links to its own installer files. That is about 31 releases a year.
Popularity and file types
The Chocolatey package has been downloaded 527,849 times. The source code on GitHub (activescott/lessmsi) has 1,771 stars. Similar programs include 7-Zip, PeaZip and WinRAR.
Project description on GitHub: “A tool to view and extract the contents of an Windows Installer (.msi) file.”
Pros / Cons
Pros
- Open source: the code can be inspected and built by anyone
- Portable: runs without installation
- Frequent updates (about 31 a year)
In short: lessmsi is an open-source archiver tool for Any CPU PCs. It is actively maintained.
Is lessmsi safe to download?
- The file is served by github.com, the publisher’s own domain
- The download link uses HTTPS
- A SHA256 hash is published, so you can verify the file:
5B4E187E74B184AD3A63CCF06C3D17DAE2B8C4B6C298A996DBD51A9F6DB29D21· Open the VirusTotal report for this hash - The link has not been checked yet
- 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 activescott/lessmsi repository on GitHub by the Open Source Security Foundation, last run on October 19, 2026.
- Code review10
- Licence declared10
- Actively maintained3
- No binaries in the repository0
- OpenSSF Best Practices badge0
- Security policy0
- 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 34 versions ›34 versions over 1 year · about 31 a year
| Version | Date | Size | Files |
|---|---|---|---|
| 2.12.9Latest | April 2, 2026 | — | Any CPU ZIP |
| 2.12.8 | April 2, 2026 | — | Any CPU ZIP |
| 2.12.7 | March 30, 2026 | — | Any CPU ZIP |
| 2.12.6 | March 29, 2026 | — | Any CPU ZIP |
| 2.12.5 | February 21, 2026 | — | Any CPU ZIP |
| 2.12.4 | February 20, 2026 | — | Any CPU ZIP |
| 2.12.3 | February 20, 2026 | — | Any CPU ZIP |
| 2.12.0 | February 15, 2026 | — | Any CPU ZIP |
Install from the command line
Silent install ›winget install --id activescott.lessmsi -echoco install lessmsi -yRelated guide: How to use winget: install and update apps
Information
- Publisher
- Scott Willeke
- Category
- Archivers
- Licence
- MIT
- Price
- Free
- Source code
- github.com/activescott/lessmsi
- Written in
- C#
- Requires
- Windows 11 / 10
- Architecture
- Any CPU
- Installer
- Portable
- Version
- 2.12.9
- Released
- April 2, 2026
- Added to the catalogue
- February 28, 2025
- Versions listed
- 34
- Updates / year
- 31.2
- Chocolatey downloads
- 527,849
- GitHub stars
- 1,771
- GitHub forks
- 187
- Website
- github.com
- winget ID
- activescott.lessmsi
- Chocolatey package
- lessmsi
Ratings and reviews
No reviews yet. Be the first to rate it.
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Frequently asked questions
Is lessmsi free?
Yes. lessmsi is open-source software under the MIT licence.
Is lessmsi safe to download?
The download comes from github.com, which belongs to the publisher; 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 lessmsi 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.
Does lessmsi run on ARM (Windows on Arm)?
The installer is architecture-neutral.
Where can I download an older version of lessmsi?
The versions page lists all 34 versions with links to their official installer files, back to February 28, 2025.
Can I use lessmsi without administrator rights?
Yes, it is portable: unpack and run it.
What are alternatives to lessmsi?
7-Zip, PeaZip, WinRAR, Zstandard and UPX. The alternatives page compares them.
