Klipper Input Shaper & Acceleration Calculator
Determine max recommended acceleration (mm/s²) based on ADXL345 resonance frequency (Hz) and shaper filter type.
MAX_SMOOTHING.How to read these numbers
Input shaping suppresses ringing by splitting each move into impulses timed against the axis resonance you measured. The suppression is not free: every shaper imposes some smoothing, and smoothing costs effective acceleration and fine detail. Shapers that tolerate a wider error in the frequency estimate impose more of it.
So the two outputs move against each other. The smoothing figure is a relative index for
ranking the three shapers at one frequency, not a value to paste into a
MAX_SMOOTHING argument. A lower resonant frequency makes every option worse,
which is a mechanical result rather than a firmware one: a heavy toolhead or a flexing
gantry is not repaired by a shaper choice.
What this is not
This is an approximation for sizing an expectation before you commit a value, not a substitute for a measurement. Klipper's own shaper calibration runs against the resonance data from your accelerometer and prints a recommended shaper, frequency and acceleration ceiling for your machine. Where the two disagree, the calibration output is the authority.
The measured frequency this asks for comes from an accelerometer on the toolhead, not from a spec sheet. Two printers of the same model will not give the same answer.
Where the input comes from
- Klipper input shaper setup with an ADXL345 wiring, config stanzas, and the calibration commands that produce the frequency this needs.
- How Klipper works: host, MCU, and printer.cfg how the host plans motion, the MCU schedules hardware operations, and configuration changes take effect.
- Klipper hardware requirements which accelerometers Klipper supports and where to plug one in.
- Klipper vs Marlin why a measured resonance profile is the clearest difference between the two firmwares.