G90/G91: Absolute / incremental
Defines whether coordinates are absolute or incremental.
For reference only: syntax changes with the control, the post-processor and the machine parameters. Check the official manual and run a simulation before cutting. Legal notice.
- Family
- Coordinates
- Machine
- Milling, Turning, Mill-turn
- Risk
- High
- Example
- G90 G54 / G91 X10
G90 G54 / G91 X10Machine: Milling, Turning, Mill-turnRisk: High
ISO común · Fanuc · Haas
G90 / G91- ISO común: A forgotten G91 can displace all subsequent movements.
Heidenhain
Coordenadas absolutas o incrementales con prefijos específicos- The form depends on the control's conversational or ISO mode.
May be modal depending on the control and machine setup. Always confirm in the manufacturer's manual before using it in production.
Related:G54
Other codes in Coordinates
See the full list of G and M codesFrequently Asked Questions (FAQ)
What does G90/G91 mean in a CNC program?
Defines whether coordinates are absolute or incremental. In the catalogue it appears as "Absolute / incremental", within the Coordinates family.
How is G90/G91 written on each control?
Fanuc: G90 / G91 · Haas: G90 / G91 · Heidenhain: Coordenadas absolutas o incrementales con prefijos específicos · ISO común: G90 / G91. The exact syntax depends on the control version and the machine parameters: always confirm with the manufacturer's manual.
Can you give me an example of G90/G91?
G90 G54 / G91 X10 — Defines whether coordinates are absolute or incremental.
Which other codes is G90/G91 combined with?
In practice G90/G91 appears alongside these codes: G54, G92. It is worth reading them together, because the state one leaves behind conditions what the next one does.
Which machines use G90/G91?
G90/G91 is used in: Milling, Turning, Mill-turn.
What should you watch out for with G90/G91?
High risk: a mistake here can cause a crash, a broken tool or an out-of-tolerance part. Simulate the program and dry-run it before cutting.
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