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G54.APP

G-Code Viewer & CNC Simulator

Real-time G-code viewer and CNC stock simulator that runs in your browser. Drop in a .nc or .gcode file to visualize toolpaths, simulate material removal, and verify programs before they hit the machine — all at 60+ frames per second. Free, no install, no account.

What it does

Real-time toolpath playback at 60+ fps with smooth scrubbing through any point in the program.
Stock removal simulation — material disappears as the tool cuts, with correct geometry for flat, ball, bullnose, taper, and V-bit tools.
Tool library with customizable diameters, flute geometry, and taper angles for accurate stock-removal previews.
Built-in G-code editor with syntax highlighting and live autocomplete for every G and M code — sourced from a cross-control reference covering LinuxCNC, GRBL, Centroid, FANUC, Mach 3, and Mach 4.
Hack panel — translate, rotate, flip, swap tools, and remap feedrates on the loaded program without leaving the app or going back to CAM.
Work-offset (G54) origin picker covering all 27 anchor positions on rectangular stock.
Desktop builds for macOS and Windows that run offline.

Share programs by link

Loaded a file you want to send to someone? Click the share icon and G54.APP uploads a copy to its share servers, then hands back a short URL that opens the program — toolpath, tool settings, stock setup and all — on any device with a modern browser. The recipient doesn't need an account, doesn't need to install anything, and can just click the link to load your file directly into their browser.

Uploaded files are accessible to anyone with the link and deleted automatically after 30 days. Only the G-code source, tool definitions, and stock setup are uploaded — no personally identifiable information beyond that is captured. Files up to 25 MB compressed (roughly 75 MB of raw G-code) are supported.

Supported file types

G54.APP reads standard G-code variants used by most 3-axis CNC mills and routers, including .nc, .gcode, .tap, and .cnc files exported from Fusion 360, Mastercam, HSMWorks, Carbide Create, and similar CAM software.

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