Convert G-code to STL — Reconstruct the 3D Model from a Toolpath
Upload a G-code file and get back an STL mesh rebuilt from its extrusion moves, ready to view, measure or remodel when the original model is gone. Expect a close copy of what the printer would lay down, supports and infill included, rather than the designer's source file.
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Why Convert GCODE to STL?
G-code is a list of machine instructions: move here, push out this much filament, start the next layer. It holds no surfaces or triangles, so Blender, Fusion 360 or a slicer's model view cannot open it as a shape. Once the original STL or 3MF is lost, the print file on an SD card or in the printer's history is often the only copy of the part left.
Our server reads the file line by line and keeps only the moves that deposit plastic, which are the ones where the extruder position goes up. Travel moves, retractions and Z-hops add no material, so they are left out. When the slicer wrote layer markers such as ;LAYER_CHANGE or ;LAYER:0, the start and end scripts are dropped as well, which removes the purge line most printers draw along the edge of the bed. Every remaining move is traced into a 3D grid, a closed surface is wrapped around those traces, and the result is saved as binary STL.
What you get is the printed object, not the design behind it. Supports, brims, skirts and the infill pattern are all extruded, so they are all in the mesh, with the infill sitting as a lattice inside the walls. Detail is set by the grid: the longest side of the print is divided into at most 250 steps and a step is never smaller than 0.3 mm, so a small figurine keeps more detail than a part that fills the bed, and individual layer lines blend together. Arc moves are read by their end point only, so curves written as G2/G3 come out as straight segments.
Searches like convert gcode back to stl or gcode to 3d model bring makers who kept a print file but lost the model, people checking what a downloaded G-code will really print, and owners of FlashForge or Prusa printers whose slicer saved a .gx or binary .bgcode file. Both of those are accepted here, along with .g and .gco.
How to Convert GCODE to STL
- Find the G-code exactly as the printer would receive it. Plain .gcode, .g and .gco work, and so do FlashForge .gx files and PrusaSlicer binary .bgcode; a .bgcode that Prusa Connect encrypted for one specific printer cannot be decoded.
- If you can still re-slice, switch off arc fitting (the setting is usually called Arc fitting or ArcWelder) before exporting, so curves are written as short straight moves the reconstruction can follow closely.
- Drop the file on the upload area above. You can add up to 10 G-code files in one batch without a paid plan, and each one comes back as its own STL.
- Let the server process it. Typical slicer files finish in a few seconds, while long multi-hour prints take noticeably longer.
- Download the STL and open it in a mesh viewer or editor. Trim away supports and the brim there before you reprint or remodel the part.
Key Conversion Features
- Rebuilds geometry only from extruding moves; travel, retraction and Z-hop moves are skipped
- Drops the start and end scripts, and the bed-edge purge line, when the file carries layer markers
- Follows absolute and relative positioning (G90/G91, M82/M83) and the extruder resets (G92) slicers insert every layer
- Takes .gcode, .g, .gco, FlashForge .gx and Prusa binary .bgcode on the same page
- Outputs a closed binary STL whose detail grid scales with the print, never finer than 0.3 mm
Video Tutorial
Convert GCODE to STL online. Reconstruct 3D mesh from G-Code toolpaths for 3D printing and rapid prototyping. Free, fast, no installation required. 📌 Convert GCODE to STL free: https://miconvert.com
Frequently Asked Questions
Can you convert G-code back to STL?
Yes, as a reconstruction. G-code never contained the original triangles, so no tool can recover the exact source file. What you get is a mesh of the plastic the printer would deposit, which is usually close enough to measure, reprint, or use as a reference for remodeling.
Why are supports, a brim and infill inside my STL?
Because the printer extrudes them, and the converter rebuilds everything that is extruded during the print. To get a cleaner shell, slice the original again with supports and brim turned off before converting, or cut them away afterwards in a mesh editor such as Meshmixer or Blender.
Does it work with CNC router or laser G-code?
It accepts it. When a file has no extrusion (E) values at all, every feed move (G1, G2, G3) is traced and rapid G0 moves are skipped. The result is a thin tube that follows the tool's center line, plunges included. It does not model the cutter's width or the material removed, so it shows where the tool went, not the finished part.
Why did my file fail with "No movement/extrusion commands found"?
This is the most common failure on this page, and it means the parser found no moves that extrude. Usually the upload is not the print file itself: a start or end script, a printer macro, a download that was cut short, or a project file renamed to .gcode. Export the complete G-code from your slicer again and upload that file.
Are colors and multiple extruders kept?
No. Tool changes are not tracked, so moves from every extruder end up in one uncolored mesh, and a prime or wipe tower printed next to the part becomes part of the STL as well. STL has no way to store color in any case.
How accurate are size and position?
Coordinates come straight from the G-code, so overall dimensions match the print and the mesh sits where it was on the printer's bed rather than at the origin; center it in your software if needed. Fine features are limited by the reconstruction grid and a fixed bead about 0.4 mm wide, so thin walls, small lettering and sharp corners come out rounded.
Is my G-code processed in the browser, and is it kept?
No, conversion runs on our servers. The uploaded G-code is deleted as soon as the conversion finishes, and the STL stays available for download for about four hours before an automatic cleanup removes it.
Is there a file size limit?
Without an account each file can be up to 50 MB, and signing in to a free account raises that to 100 MB. Most slicer G-code is well under either limit.