QR code to STL generator

To 3D print a QR code that scans, use two contrasting filaments (black code on a white plate is best), keep every module at 1 mm or more so a 0.4 mm nozzle prints clean squares, leave a plain border around the code, and switch colours exactly at the top of the plate. This generator builds the plate and the code as separate closed solids and tells you the layer to change filament on.

Raised code or flush inlay

Raised is the easy choice. The plate prints in the light colour, you change filament once, and the code prints on top in the dark colour. For a flush code, download the two-colour 3MF and assign one filament to each part in Bambu Studio, OrcaSlicer or PrusaSlicer. The inlay plate STL on its own is a debossed code, handy if you want to fill the pockets with paint.

Size it by the module

Modules are the small squares. With a 0.4 mm nozzle, squares under about 1 mm lose their corners and the code stops scanning, so the tool warns you below that. These widths include a 2-module border; the plate's own margin adds a little more.

The numbers are for error correction M; Q and H add modules. The tool shows the exact version and module size as you change the content and the plate.

Change filament at the right layer

For a raised code, the change happens where the plate ends. With a 1.6 mm plate and 0.2 mm layers, the plate is layers 1 to 8 and the code starts on layer 9 at Z 1.6 mm. The tool calculates this for your thickness and layer height. In Bambu Studio, OrcaSlicer and PrusaSlicer, slice, move the layer slider in the preview to that layer and add a filament or colour change there. In Cura, the Pause at Height post-processing script does the same job. The filament swap height guide explains how slicers count layers if your first layer is a different height.

Print settings that help it scan

• Print flat on the bed, code facing up.
• Use 0.2 mm layers or finer so the code's top surface is clean.
• Slow the top layers slightly if your printer leaves stringing between modules.
• Check the first test with two phones before printing a batch. If it fails, make the plate wider, use a shorter link or raise the error correction one step.

Want the same code engraved instead? The QR code generator for laser engraving exports SVG, DXF and PNG at real size, and engraves the background automatically on materials that mark light.