Repo Compare › 3D printer firmware
Marlin vs Klipper vs FluidNC
A side-by-side look at how actively Marlin, Klipper and FluidNC are developed on GitHub — popularity, contributor base, commit activity and how quickly issues and pull requests move.
What the numbers say
- Marlin is the most-starred of the 3, with 18k stars — about 6.8× FluidNC's 2.6k.
- Over the 52 weeks to the snapshot, Marlin recorded the most commits (667), against 328 for FluidNC.
- Marlin has closed or merged the most pull requests in its lifetime: 13k.
- Relative to its popularity, Klipper carries the lightest open-issue load: 0.1 open issues per 1,000 stars, versus 45.8 for FluidNC.
Head-to-head
Snapshot taken 30 September 2026.
| Metric | Marlin Active | Klipper Active | FluidNC Active |
|---|---|---|---|
| Stars | 18k | 12k | 2.6k |
| Forks | 20k | 6.0k | 653 |
| Contributors | 1.3k | 506 | 76 |
| Commits, last 52 weeks | 667 | 440 | 328 |
| Open issues | 650 | 1 | 118 |
| Open pull requests | 147 | 261 | 35 |
| Closed / merged PRs | 13k | 3.0k | 883 |
| Watchers | 866 | 374 | 93 |
| Last push | 30 Sep 2026 | 28 Sep 2026 | 29 Sep 2026 |
| Latest release | 2.1.2.8 (Jun 2026) | none published | v4.1.1 (Sep 2026) |
| Main language | C++ | C | C++ |
| Licence | GPL-3.0 | GPL-3.0 | Not detected by GitHub |
| Created | Aug 2011 | May 2016 | Aug 2021 |
Bold marks the highest value in a row. “Active / Slowing / Dormant” is a simple heuristic from how recently code was pushed and open issues per star — a starting point, not a verdict. Stars measure popularity, not quality.
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