Markeron
Markeron is a free, open-source PDF tool for Windows and macOS. Lightweight (~1.5 MB) open-source screen annotation with click-through mode and keyboard-first shortcuts. It has 1,157 GitHub stars and is released under the MIT license. Its source code is on GitHub at ifer47/markeron.
- macOS
- Windows
- PDF editors & tools
- Actively maintained
About Markeron
Lightweight screen annotation tool (~1.5 MB) — press a hotkey ( keyboard-first ) to instantly draw, highlight, and annotate anywhere on your desktop. Built for demos, teaching, meetings, and screen recording. Free & open source. If MarkerOn saves you time in demos, teaching, or meetings, sponsor on Afdian — every contribution helps keep the project maintained.
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What is Markeron?
Markeron is a free, open-source PDF tool for Windows and macOS. Lightweight (~1.5 MB) open-source screen annotation with click-through mode and keyboard-first shortcuts. It has 1,157 GitHub stars and is released under the MIT license. Its source code is on GitHub at ifer47/markeron.
Is Markeron free and open source?
Yes. Markeron's source code is public on GitHub under the MIT license, which is OSI-approved or FSF-free, so you can use, copy and change it for free.
How do I install Markeron?
Download the installer for Windows and macOS from its GitHub Releases page (latest: v2.11.1) or the project website.
Is Markeron still maintained?
The repository's most recent commit was on Oct 8, 2026. appsgit only lists apps whose repository had a commit in the last six months.