OctoPrint vs Klipper: Host vs Firmware, or Run Both?

OctoPrint and Klipper are not rivals. OctoPrint is a print host that sends G-code to your printer’s existing firmware, while Klipper replaces that firmware and moves motion planning onto a Raspberry Pi. Pick OctoPrint to monitor and control a printer that already prints well, and pick Klipper for input shaping and speed. You can also run both.

“OctoPrint vs Klipper” is the most common framing of this question and it is the wrong one. The two projects do not occupy the same layer. Comparing them directly is like comparing a web browser to an operating system, and most of the confusion in forum threads on this topic comes from that category error rather than from any real disagreement about the software.

Here is what each thing actually is, and then the decision that follows.

What OctoPrint is

OctoPrint is a host. It runs on a separate computer, usually a Raspberry Pi, and talks to your printer over USB serial. It uploads G-code, streams it to the printer line by line, shows temperatures and progress, serves a camera feed, and hosts a large plugin ecosystem.

For a workflow built around extensions, the plugin ecosystem is OctoPrint’s main advantage. The official plugin repository listed 406 plugins when checked in October 2026. Check the functions you use before deciding whether a firmware change also needs an interface change.

Crucially, OctoPrint does not change how your printer moves. Motion planning, acceleration, and every kinematic decision still happen inside the printer’s own firmware, which on most consumer machines is Marlin. OctoPrint is a very capable remote control and monitoring layer bolted onto whatever firmware is already there.

What Klipper is

Klipper is a firmware replacement with a split architecture. The microcontroller on the printer’s control board is reflashed with a minimal Klipper binary whose only job is to execute precisely timed step events. All the hard work, parsing G-code, look-ahead, acceleration planning, kinematics, is moved onto a Linux host, typically the same class of Raspberry Pi that would otherwise run OctoPrint.

That is the whole idea. An 8-bit or modest 32-bit control board cannot compute complex motion in real time, but it can execute a schedule that a much faster computer has already worked out. Moving the planner off the printer is what makes Klipper’s headline features possible.

Klipper itself has no user interface. What people mean when they say they “run Klipper” is a stack:

• Klipper — the firmware and host motion planner
• Moonraker — the API server that exposes Klipper over HTTP and WebSocket
• Mainsail or Fluidd — the web interface, roughly the equivalent of OctoPrint’s UI
• optionally KlipperScreen for a local touchscreen

So the honest comparison is OctoPrint plus Marlin against Klipper plus Moonraker plus Mainsail.

What the switch actually buys you

The Klipper documentation lists the features that come from having a real computer doing motion planning. The ones that change printed output are:

Input shaping. Klipper can cancel the specific resonant frequencies of your printer’s frame and gantry, which is what causes ringing or ghosting after sharp corners. With an accelerometer attached to the toolhead you measure those frequencies once and configure the compensation. This is the single biggest quality difference and it is not something OctoPrint can offer, because it is a motion-planning function. Marlin 2.1.2 and later has a simpler ZV input shaper, set with M593 when the build enables it; Klipper adds the accelerometer measurement. Its resonance guide supports ADXL345, MPU-9250, LIS2DW and LIS3DH accelerometers, and SHAPER_CALIBRATE recommends a shaper type and frequency for each axis.

Pressure advance. Compensating for the pressure lag in a bowden or direct-drive extruder so corners and line starts get the right amount of material. Marlin has linear advance, which addresses the same problem, and its K factor is set live with M900 once LIN_ADVANCE is compiled in. A reflash is only needed when the build lacks LIN_ADVANCE. Klipper’s pressure advance is tunable live as well.

Configuration without reflashing. Klipper’s entire configuration lives in a printer.cfg text file on the host. Change a value, restart the service, done. On Marlin, changing most settings means editing C++ headers, recompiling, and flashing a new binary. For anyone who tinkers, this alone is worth the migration.

Higher usable speeds. Because the planner is not constrained by the control board’s CPU, complex geometry does not starve the move buffer the way it can on an 8-bit board.

Macros. Klipper macros are defined in configuration and can call each other, read variables, and run conditionals. They replace a large chunk of what OctoPrint plugins exist to do.

What the switch costs you

A flashing step with real risk of a bad afternoon. You compile a Klipper binary for your specific microcontroller and flash it. Get the board variant wrong and the printer is unresponsive until you fix it. This is recoverable but it is not a one-click operation.

Your stock screen probably stops working. Many stock LCD controllers are not supported, or are supported in a degraded form. KlipperScreen on a small touchscreen is the usual replacement and it is another thing to buy and configure.

Configuration is now your problem. printer.cfg has to describe your printer completely: pins, thermistor types, kinematics, endstops, limits. Community configurations exist for common machines and they are usually the starting point, but a config that is subtly wrong for your hardware can drive a heater or a motor somewhere you do not want it. Read what you are pasting.

You lose the OctoPrint plugin catalogue. Mainsail and Fluidd are excellent interfaces but they are not extensible in the way OctoPrint is. If your workflow depends on specific plugins, check for equivalents first.

Warranty and support. Some manufacturers treat a firmware replacement as the end of support for the machine.

Side by side

OctoPrint vs Mainsail

Mainsail does not replace OctoPrint on a stock printer. It is a Klipper-only web interface that talks to Moonraker, so it cannot drive a Marlin machine over USB the way OctoPrint does. Choosing Mainsail means choosing Klipper first; the interface comes with that decision.

Once you are on Klipper, Mainsail’s feature list covers much of what OctoPrint users install plugins for: webcam and timelapse, bed mesh and G-code viewers, print history, power device control, object exclusion and several printers in one interface. Your slicer keeps working too, because Moonraker’s [octoprint_compat] section emulates enough of the OctoPrint API for PrusaSlicer derivatives, and Cura with its OctoPrint plugin, to upload as if to OctoPrint. Camera hardware from the webcam guide carries over as well.

Mainsail vs Fluidd

Mainsail and Fluidd do the same job on the same plumbing: both are GPL-3.0 interfaces (Mainsail, Fluidd) that talk to Klipper through Moonraker, so either controls any Klipper printer. Pick on layout preference. The practical tie-breaker is installation, because only Mainsail still ships a maintained flashable image.

To compare without installing anything, add *://app.fluidd.xyz to cors_domains in moonraker.conf; the hosted Fluidd build then runs in your browser and talks directly to your existing printer.

Can you run Klipper and OctoPrint together?

Yes, and a lot of people do. OctoPrint can drive a Klipper machine through a virtual serial port that Klipper exposes, with the OctoKlipper plugin adding configuration editing and log access. You keep the OctoPrint interface and plugin set while Klipper does the motion planning.

The Klipper project’s OctoPrint guide gives this order:

1. Flash OctoPi 0.17.0 or later and confirm OctoPrint loads.

2. Over SSH, install Klipper with its OctoPi script:

   cd ~
   git clone https://github.com/Klipper3d/klipper
   ./klipper/scripts/install-octopi.sh

3. In Settings, Serial Connection, add ~/printer_data/comms/klippy.serial under “Additional serial ports”, save, then reopen Settings and select it as the Serial Port.

4. In the Behavior sub-tab choose “Cancel any ongoing prints but stay connected to the printer”.

5. Connect, then send status in the Terminal tab. An error about opening the config file is expected: it means OctoPrint is talking to Klipper.

6. Build and flash the Klipper binary for your board and write printer.cfg.

7. Install OctoKlipper from the Plugin Manager; version 0.4 shipped in September 2026.

OctoPrint 2.0 adds a second route. The 2.0.0rc1 release notes move printer communication into connectors and name Moonraker alongside serial, so OctoPrint can reach a Klipper machine through the same API server Mainsail and Fluidd use. It is not stable yet: in October 2026 the current stable release was still 1.11.8, and the 2.0.0rc6 notes of 7 October still call the Moonraker Connector a work in progress.

Running both is a legitimate setup, but it is also a third configuration to maintain, and Mainsail and Fluidd have closed most of the interface gap that made it compelling. Treat it as a migration aid rather than a destination: run it while you get comfortable with Klipper, then decide whether you still need OctoPrint on top.

Note that both stacks want a host machine of the same general class, so the hardware guide applies either way. Power supply quality, storage endurance and USB cable shielding matter identically. Klipper is arguably less tolerant of a marginal host, because a starved host is now starving the motion planner rather than just the upload stream. The undervoltage and USB noise checks in the mid-print disconnect guide apply to both.

The third option: a printer that needs neither

Both of these stacks exist to add remote control, monitoring and better motion to printers that shipped without them. A newer machine may already have all three built in.

The Bambu Lab P1S is the clearest example of the closed-ecosystem answer: onboard camera, network control from the vendor’s slicer and app, input shaping done in the factory firmware, no host computer at all. The tradeoff is exactly what you would expect. You get the features immediately and you give up the ability to change how any of it works. In January 2025 a Bambu firmware update put an authorization layer in front of operations including print initiation and axis control, applied it in LAN mode as well as over the internet, and cut third-party slicers off from the network API unless they went through the vendor’s own connector software. That is the shape of the risk with a closed stack: the vendor decides what your printer is allowed to talk to, and it can decide again after you have bought it.

Prusa’s current MK-series machines take the middle path, shipping PrusaLink and Prusa Connect for network control on open firmware. Prusa sells these direct rather than through retail marketplaces, so buy from the manufacturer.

OctoPrint alternatives

The main OctoPrint alternatives are Mainsail or Fluidd once you move to Klipper, PrusaLink on recent Prusa printers, Repetier-Server for mixed fleets, and AstroPrint for cloud printing. Mainsail and Fluidd need Klipper and PrusaLink is Prusa-only, so a stock Marlin printer realistically leaves Repetier-Server, AstroPrint or OctoPrint itself.

OctoPrint vs PrusaLink

On a current Prusa, PrusaLink is built in, needs no Pi, and covers local monitoring, uploads and print control, with Prusa Connect adding remote access. OctoPrint earns its place when you want plugins. An MK3/S/+ needs a Pi either way: a Zero 2 W on the GPIO header or a Pi 3, 3+, 4 or 5 over USB. PrusaLink itself replaced Prusa’s discontinued OctoPrint-based PrusaPrint.

AstroPrint vs OctoPrint

They are not mutually exclusive. AstroPrint is a cloud platform for browser slicing, remote printing and print queues, and its OctoPrint plugin (1.7.2, March 2026) connects an existing OctoPrint host to it. The difference is where control lives: OctoPrint stays on your network, while AstroPrint routes through its servers. A vendor-run cloud is a milder version of the dependency risk described above for closed printers.

How to decide

Run OctoPrint if your printer already produces prints you are happy with and what you want is to watch it, control it from another room, and get told when something goes wrong. It is additive, reversible, and you can be running in under an hour.

Move to Klipper if you are chasing print quality or speed, you are willing to own a configuration file, and ringing or corner artifacts are what actually bother you about your output. The tuning features are real, and Klipper makes them easiest to measure and tune.

Buy a machine with it built in if you value none of the above and want prints without a project.

Whichever you pick, the safety rule does not change: neither of these is designed to sit on the open internet, both control heaters, and neither should be the only thing between a fault and a fire. Firmware-level thermal runaway protection stays enabled regardless. The safe remote access guide covers private VPN connections and an outbound relay.

FAQ

is klipper better than octoprint?

Klipper is better at motion: input shaping measured with an accelerometer, pressure advance and configuration in a text file. OctoPrint is better at being added to a printer without changing it, with hundreds of plugins and nothing to reflash. They solve different problems, so the better choice depends on whether print quality or remote control is your gap.

do i need octoprint if i run klipper?

No. Klipper with Moonraker and Mainsail or Fluidd already gives you a web interface, webcam view, slicer uploads and print history, so OctoPrint is optional on a Klipper machine. Add it only if a specific OctoPrint plugin has no Klipper macro or Moonraker equivalent, and connect it through the virtual serial port described above.

what is octoklipper?

OctoKlipper is the OctoPrint plugin for printers running Klipper. It adds a browser editor for Klipper’s configuration, buttons to restart the Klipper host and microcontroller, macro buttons, PID tuning, a bed leveling helper and a Klipper-only log view. The plugin repository lists it as compatible with OctoPrint 1.3.8 and later.

is astroprint still free?

Yes, for the basic plan. When AstroPrint joined forces with Print&Go in September 2024, it said the basic plan would not get a price tag, and its OctoPrint plugin received a 1.7.2 update in March 2026. Its site also links a plans and pricing page, so check current terms before committing a print farm to it.