O2 is a safe and flexible archive for personal data, such as contacts, accounts, credit cards, Wi-Fi settings, and everything that comes to your mind.
Publisher’s description
What is O2?
O2 by maurizuki is open-source Windows software in the password managers category. It is written in Pascal.
Installation and requirements
The publisher provides EXE (Inno Setup) installers for 32-bit Windows. Installation asks for administrator rights. A silent install is possible with the installer’s documented switches.
Updates and version history
The current version is 3.4.0, released on August 28, 2026. The version history goes back to May 28, 2021: 14 releases, all linked to the official files. That is about 2.7 releases a year.
Popularity and file types
The source code on GitHub (maurizuki/O2) has 6 stars. On Windows it registers 1 file type, including .o2. Similar programs include Bitwarden, KeePassXC and KeeWeb.
Project description on GitHub: “Welcome to O2, a new way to store and organize your personal data.”
Pros / Cons
Pros
- Open source: the code can be inspected and built by anyone
- Documented silent install
- Updated in the last two months
Cons
- No native ARM64 build
- 32-bit only
- Installation needs administrator rights
In short: O2 is an open-source password manager tool for 32-bit PCs. Administrators can deploy it unattended.
Is O2 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:
CB8EBB9314B170775E497AF7D04C72C265090BC6108778777CBA6EE9D6700960· 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
Recent versions
All 14 versions ›14 versions over 5 years · about 2.7 a year
| Version | Date | Size | Files |
|---|---|---|---|
| 3.4.0Latest | August 28, 2026 | — | 32-bit EXE (Inno Setup) |
| 3.3.2 | April 2, 2026 | — | 32-bit EXE (Inno Setup) |
| 3.3.1 | January 19, 2026 | — | 32-bit EXE (Inno Setup) |
| 3.3.0 | January 7, 2026 | — | 32-bit EXE (Inno Setup) |
| 3.2.0 | May 21, 2025 | — | 32-bit EXE (Inno Setup) |
| 3.1.0 | January 23, 2025 | — | 32-bit EXE (Inno Setup) |
| 3.0.0 | June 11, 2024 | — | 32-bit EXE (Inno Setup) |
| 2.4.0 | January 13, 2024 | — | 32-bit EXE (Inno Setup) |
Install from the command line
Silent install ›winget install --id maurizuki.O2 -eO2-3.4-setup.exe /VERYSILENT /SUPPRESSMSGBOXES /NORESTART /SP-Related guide: How to use winget: install and update apps
Information
- Publisher
- maurizuki
- Category
- Password managers
- Licence
- MPL-2.0 License
- Price
- Free
- Source code
- github.com/maurizuki/O2
- Written in
- Pascal
- Requires
- Windows 11 / 10
- Architecture
- 32-bit
- Installer
- EXE (Inno Setup)
- Version
- 3.4.0
- Released
- August 28, 2026
- Added to the catalogue
- May 28, 2021
- Versions listed
- 14
- Updates / year
- 2.7
- GitHub stars
- 6
- GitHub forks
- 2
- Website
- github.com
- winget ID
- maurizuki.O2
File types it opens (1)
Ratings and reviews
No reviews yet. Be the first to rate it.
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Frequently asked questions
Is O2 free?
Yes. O2 is open-source software under the MPL-2.0 License licence.
Is O2 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 O2 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 O2 be installed silently?
Yes. The silent install page lists the exact command for each installer.
Does O2 run on ARM (Windows on Arm)?
There is no ARM64 build; Windows 11 on Arm can run the 32-bit version through emulation.
Where can I download an older version of O2?
The versions page lists all 14 versions with links to their official installer files, back to May 28, 2021.
What are alternatives to O2?
Bitwarden, KeePassXC, KeeWeb, Password Safe and 1Password. The alternatives page compares them.
