Understanding G-Code: A Simple Guide for CNC Beginners

May 16, 2026

G-Code is the programming language used by CNC machines. It tells the machine how to move, where to cut, and at what speed. While you don’t need to write G-Code manually if you use CAM software, understanding the basics helps in better control and troubleshooting.

Common G-Code Commands

• G00 – Rapid positioning (fast movement without cutting)
• G01 – Linear interpolation (straight line cutting)
• G02 – Circular interpolation clockwise
• G03 – Circular interpolation counter-clockwise
• G90 – Absolute positioning mode
• G91 – Incremental positioning mode
• M03 – Spindle ON (clockwise)
• M05 – Spindle OFF

Why Learn G-Code?

Knowing basic G-Code helps you understand what your CAM software is generating. It also allows you to make small manual adjustments when needed and debug issues more effectively.

Final Thoughts

You don’t need to become an expert in G-Code to operate a CNC machine. However, having a basic understanding will make you more confident and capable as a CNC user.

Akriti Precision Systems machines work well with popular control software like Universal G-Code Sender (UGS), making it easier for beginners to get started.