M851 - Z Probe Offset


Set the vertical distance from the nozzle to the Z probe trigger-point.

The easiest way to get the value is to:

  • Home the Z axis.
  • Raise Z and deploy the probe.
  • Move Z down slowly until the probe triggers.
  • Take the current Z value and negate it. (5.2 => -5.2)
  • Set with M851 Z-5.2 and #define Z_PROBE_OFFSET_FROM_EXTRUDER -5.2.


The default (factory) value is set by Z_PROBE_OFFSET_FROM_EXTRUDER. In Snapmaker 2.0 firmware, the parameter has no effect.


M851 Z<float>

Z probe Z offset


Set a reasonable offset for an inductive probe

M851 Z-2.0

A probe that is triggered by the nozzle itself

M851 Z1.2