Updating Firmware & PrusaSlicer Profiles

Checking your current firmware version

The MK4's system menu shows the installed firmware version under its info screen. Compare against the latest stable release on Prusa's website.

Updating firmware

1. Download the correct firmware build for the MK4 specifically — not the MK3S+ or MK3.5, which are different hardware.
2. Copy it to the root of a USB drive.
3. Insert it and follow the on-screen update prompt; the printer flashes automatically.
4. Re-run Input Shaping and first-layer calibration after a major firmware update, since improvements to these routines occasionally require redoing them once.

Tip: Prusa ships meaningful print-speed and calibration improvements in MK4 firmware updates fairly often — reading the changelog is worth it on this printer specifically.

PrusaSlicer profiles

PrusaSlicer's MK4 print profiles already assume input shaping and the Nextruder's direct-drive extrusion characteristics — don't copy over MK3S+ custom profiles wholesale, since retraction and speed settings tuned for the older printer are usually too conservative for the MK4.

Custom filament profiles

As with the MK3S+, save your own tuned settings as a new profile rather than editing a stock one — stock profiles refresh on PrusaSlicer's own updates and any direct edits get lost.