G-Code and M-Code Command List for CNC Mills [ Examples & Tutorials ]

Complete g code list with m-codes for milling in the Fanuc, LinuxCNC, GRBL, and Haas dialects. We give a quick definition for all g code commands along with a link to tutorials and examples of how to use it. Click the g-code link (if any) to visit a tutorial from our popuplar Online Free G-Code Training that shows examples and teaches how to program CNC machines using the g-code.

G Codes

Code	Category	Function	Notes
G00	Motion	Move in a straight line at rapids speed.	XYZ of endpoint
G01	Motion	Move in a straight line at last speed commanded by a (F)eedrate	XYZ of endpoint
G02	Motion	Clockwise circular arc at (F)eedrate	XYZ of endpoint IJK relative to center R for radius
G03	Motion	Counter-clockwise circular arc at (F)eedrate	XYZ of endpoint IJK relative to center R for radius
G04	Motion	Dwell: Stop for a specified time.	P for milliseconds X for seconds
G05	Motion	FADAL Non-Modal Rapids
G09	Motion	Exact stop check

G10	Compensation	Programmable parameter input
G15	Coordinate	Turn Polar Coordinates OFF, return to Cartesian Coordinates
G16	Coordinate	Turn Polar Coordinates ON
G17	Coordinate	Select X-Y plane
G18	Coordinate	Select X-Z plane
G19	Coordinate	Select Y-Z plane
G20	Coordinate	Program coordinates are inches
G21	Coordinate	Program coordinates are mm
G27	Motion	Reference point return check
G28	Motion	Return to home position
G29	Motion	Return from the reference position
G30	Motion	Return to the 2nd, 3rd, and 4th reference point
G32	Canned	Constant lead threading (like G01 synchronized with spindle)
G40	Compensation	Tool cutter compensation off (radius comp.)
G41	Compensation	Tool cutter compensation left (radius comp.)
G42	Compensation	Tool cutter compensation right (radius comp.)
G43	Compensation	Apply tool length compensation (plus)
G44	Compensation	Apply tool length compensation (minus)
G49	Compensation	Tool length compensation cancel
G50	Compensation	Reset all scale factors to 1.0
G51	Compensation	Turn on scale factors
G52	Coordinate	Local workshift for all coordinate systems: add XYZ offsets
G53	Coordinate	Machine coordinate system (cancel work offsets)
G54	Coordinate	Work coordinate system (1st Workpiece)
G55	Coordinate	Work coordinate system (2nd Workpiece)
G56	Coordinate	Work coordinate system (3rd Workpiece)
G57	Coordinate	Work coordinate system (4th Workpiece)
G58	Coordinate	Work coordinate system (5th Workpiece)
G59	Coordinate	Work coordinate system (6th Workpiece)
G61	Other	Exact stop check mode
G62	Other	Automatic corner override
G63	Other	Tapping mode
G64	Other	Best speed path
G65	Other	Custom macro simple call
G68	Coordinate	Coordinate System Rotation
G69	Coordinate	Cancel Coordinate System Rotation
G73	Canned	High speed drilling cycle (small retract)
G74	Canned	Left hand tapping cycle
G76	Canned	Fine boring cyle
G80	Canned	Cancel canned cycle
G81	Canned	Simple drilling cycle
G82	Canned	Drilling cycle with dwell (counterboring)
G83	Canned	Peck drilling cycle (full retract)
G84	Canned	Tapping cycle
G85	Canned	Boring canned cycle, no dwell, feed out
G86	Canned	Boring canned cycle, spindle stop, rapid out
G87	Canned	Back boring canned cycle
G88	Canned	Boring canned cycle, spindle stop, manual out
G89	Canned	Boring canned cycle, dwell, feed out
G90	Coordinate	Absolute programming of XYZ (type B and C systems)
G90.1	Coordinate	Absolute programming IJK (type B and C systems)
G91	Coordinate	Incremental programming of XYZ (type B and C systems)
G91.1	Coordinate	Incremental programming IJK (type B and C systems)
G92	Coordinate	Offset coordinate system and save parameters
G92 (alternate)	Motion	Clamp of maximum spindle speed	S
G92.1	Coordinate	Cancel offset and zero parameters
G92.2	Coordinate	Cancel offset and retain parameters
G92.3	Coordinate	Offset coordinate system with saved parameters
G94	Motion	Units per minute feed mode. Units in inches or mm.
G95	Motion	Units per revolution feed mode. Units in inches or mm.
G96	Motion	Constant surface speed
G97	Motion	Cancel constant surface speed
G98	Canned	Return to initial Z plane after canned cycle
G99	Canned	Return to initial R plane after canned cycle

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M Codes
	Code	Category	Function	Notes
	M00	M-Code	Program Stop (non-optional)
	M01	M-Code	Optional Stop: Operator Selected to Enable
	M02	M-Code	End of Program
	M03	M-Code	Spindle ON (CW Rotation)
	M04	M-Code	Spindle ON (CCW Rotation)
	M05	M-Code	Spindle Stop
	M06	M-Code	Tool Change
	M07	M-Code	Mist Coolant ON
	M08	M-Code	Flood Coolant ON
	M09	M-Code	Coolant OFF

	M17	M-Code	FADAL subroutine return
	M29	M-Code	Rigid Tapping Mode on Fanuc Controls
	M30	M-Code	End of Program, Rewind and Reset Modes

	M97	M-Code	Haas-Style Subprogram Call
	M98	M-Code	Subprogram Call
	M99	M-Code	Return from Subprogram

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G Code Commands FAQ

How many G codes are there?

There are about 100 g code commands, give or take. There are many dialects of g-code, and some have proprietary g-codes.

What are G Codes in CNC Machines?

This page lists all the G code commands and tells what they do and also gives a link to tutorials and examples. G codes are single letter commands that tell the CNC machine what to do. They may command motion (i.e. tell the machine where to cut) or do things like turn the spindle on or off.

Is learning G-Code hard?

Learning g-code isn’t very hard. We have a complete free online g-code tutorial to teach you as well as a g-code simulator that makes learning easy.

Why are G Codes used?

G Codes make CNC Machines programmable, which gives them the flexible to make almost any part.

What is the difference between G codes and M codes?

G-Codes are about Geometry while M-Codes are about Machine functions.

Do all CNC machines use G-code?

Not all CNC machine use G-Code. Some may have both g-code and other ways of programming, for example alternate languages such as Mazak’s Mazatrol or Conversational Programming. Others, may have an alternate language and no ability to execute g-code at all.