Viewers
Free Online G-code Viewer — No Upload
A free online G-code viewer that renders .gcode/.nc toolpaths in 3D directly in your browser. Parsing runs locally — no upload, no registration.
Drag files here, or click to browse
Supports GCODE, NC, GCO, TAP, CNC, NGC
Choose fileG-code is rendered locally in your browser; nothing is uploaded. Lengths are shown in mm; inch (G20) programs are converted to mm (1 in = 25.4 mm). Large programs are parsed synchronously on the main thread — the page may be briefly unresponsive while parsing (cannot be cancelled mid-parse).
What is a G-code file?
G-code (RS-274) is the numeric control language driving CNC machines and 3D printers: motion, feed and spindle commands executed line by line.
How to preview G-code online
Drop your .gcode or .nc file below. The toolpath renders as an interactive 3D trace with cycle-time estimation — useful for verifying CAM output before machining. The file stays on your device.
Convert GCODE files
FAQ
Can I check a toolpath before machining?
Yes — the viewer reconstructs the path in 3D so you can spot surprises before they reach the machine.
Does it estimate machining time?
Yes, cycle time is estimated from feed rates in the program.
Is the G-code uploaded anywhere?
No. Parsing and rendering happen entirely in your browser.