GCode Macros

Variable Substitutions and Expressions in GCode Macros
FDM (3D Printing) variable substitutions
All Modes "pre" and "post" (header/footer)
{top} = offset in mm of bed top Y axis
{left} = offset in mm of bed left X axis
{right} = offset in mm of bed right X axis
{bottom} = offset in mm of bed bottom Y axis
All Modes "post" (footer)
{time} = job run time (printing/milling) in seconds (fractional)
{print-time} = alias for {time} ... deprecated after 2.8
{print_time} = alias for {time} ... 2.9 and beyond
3D printing / FDM mode only
"feature" macro only (as of 3.4)
{feature} = feature region of the print (brims, infill, etc)
{minx|miny|maxx|maxy} = position in mm of extents of the print area
"pre", "post", and other macros
{temp} = hot end temperature
{bed_temp} = bed temperature
{fan_speed} = active cooling fan speed (usually 0-255)
{material} = length in mm of material (filament) used
{layers} = total # of layers
{layer} = current layer number
{height} = current layer height in mm
{range(from,to)} = evaluated using {layer} and {layers}
{pos_x} = last output X position
{pos_y} = last output Y position
{pos_z} = last output Z position
{progress} = 0-100% state of print output
{tool} | {nozzle} = current tool in use
{tool_count} = number of tools used in print
{tool_used_n} = whether tool # n is used in print
{z_max} = max build height in mm
{z} = current z position
{e} = amount of filament extruded
​
Logical Code Flow (IF / ELIF / ELSE / END)
;; IF { layer >= 10 && layer <= 20 }
;; ..... inside 10-20 layer={layer}
;; ELIF { layer >= 15 && layer <= 25 }
;; ..... inside 15-25 layer={layer}
;; ELSE
;; ..... did not match previous tests layer={layer}
;; END
​
PREAMBLE control (v3.4+) allows for intro comment and config list to be re-positioned after the header or disabled. This was introduced to allow GCode output to work with Ultimaker.
;; PREAMBLE OFF
;; PREAMBLE END
​
Axis Remapping (v3.5+) allows for over-riding the default axis names. Useful for swapping axes and changing output for specific firmware targets. The format of the map is a JSON object.
;; AXISMAP {"X":"Y", "Y":"Z", "E":"E1"}
​
CAM Header Directives
Comments Rewrite (v3.8+) converts ; comments into () parenthesis format
;; COMMENT_REWRITE_PARENS
Minimize the size of GCode output (v3.8+)
;; COMPACT-OUTPUT
Set decimal precision (n = integer) (v3.8+)
;; DECIMALS = n
​
CAM variable substitutions
{tool} = CAM tool #
{tool_name} = CAM tool name
{time} = dwell time in seconds
{time_ms} = dwell time in milliseconds
{time_sec} = dwell time in seconds
{speed}  = spindle speed
{spindle}, {rpm} = spindle speed (v2.7+)
Axis Scaling (v3.7+) allows for a factor to be applied to X,Y,Z coordinates. Useful for some machines like the Roland MDX-40A that uses an unusual coordinate space. Default axis scale is 1
;; SCALE { "X":100, "Y":100, "Z":100 }
​
CAM & FDM : simple algebraic expression support
Text inside {} is evaluated algebraically with access to JS classes and methods
{Math.min(layer/layers, 0.5) + 1}
{token+n} {token-n}
Shared Profiles
API, CLI, Embedding
Last modified 4mo ago