Mainsail vs. Fluidd
Both are web-based frontends for Klipper. Neither works without Klipper and Moonraker already running. The functional differences are narrow enough that most operators will be happy with either. The decision comes down to UI preference and a small set of workflow features.
| Criteria | Mainsail | Fluidd |
|---|---|---|
| Layer coverage | Printer control (Klipper frontend) | Printer control (Klipper frontend) |
| Pricing model | Free / OSS | Free / OSS |
| Price | $0 | $0 |
| Shop size fit | Sub-$50K, $50K–$500K | Sub-$50K, $50K–$500K |
| Implementation | Installed via MainsailOS image or manually alongside Klipper and Moonraker. Straightforward if Klipper is already running | Installed via FluiddPI image or manually alongside Klipper and Moonraker. Equivalent complexity to Mainsail |
| Self-hosted | Yes | Yes |
| Open source | Yes (GPLv3) | Yes (Apache 2.0) |
| UI philosophy | Denser layout; more information visible at once. Favors operators who want full machine state on a single screen | Cleaner, more minimal layout. Slightly more approachable for operators newer to Klipper |
| Mobile experience | Functional on mobile but optimized for desktop. Monitoring works; fine-grained control is awkward on small screens | Better mobile layout than Mainsail. More usable for checking print status or making minor adjustments from a phone |
| Configuration editor | Built-in config file editor with syntax highlighting. Well-regarded by operators who tune Klipper configs frequently | Built-in config file editor. Functional but considered slightly less polished than Mainsail's implementation |
| Multi-printer support | Supported via separate instances or third-party dashboards. Not a native single-pane view | Same limitation. Neither frontend offers native multi-printer fleet management |
| Community and documentation | Larger community; more tutorials, forum threads, and plugin references available | Smaller but active community. Documentation is solid; less supplementary material than Mainsail |
Both projects are actively maintained. For current status see the Printer Control index.
The real decision
If you edit Klipper configs regularly, Mainsail's editor and denser UI will serve you better. If you're monitoring from a phone or putting a less technical operator in front of the interface, Fluidd's layout causes less friction. Neither choice locks you in -- switching frontends is a reinstall, not a reconfiguration of Klipper itself.
Related comparisons:
OctoPrint vs Klipper