QR Code Keychain Tag Generator

A fully parametric keychain tag designed in OpenSCAD. The front carries a QR code (URL, text, anything you like) and the back carries up to three lines of text that are automatically sized and rotated 90° to make the most of the available space.

Everything is exposed in the Customizer — no editing the .scad file required:

• Body size — width, height, and thickness in mm
• Corner fillet — from sharp corners all the way to a pill shape (rounded by default)
• Key ring hole — diameter and distance from the top edge
• Optional border — toggle on/off, with adjustable inset and line width
• Inlay depth — how deep the QR / text / border are engraved
• QR size and standard QR options (error correction, mask, encoding)
• Two-color rendering — body and inlay colors are separately configurable, so the model previews and slices nicely for multi-color or filament-swap printing

The QR code, back text, and border all sit flush with the surface (engraved, not raised), so the tag stays flat in your pocket. Back text is automatically mirrored so it reads correctly when you flip the keychain over.

Printing tips:

• Use a 0.4 mm nozzle or smaller; 0.2 mm layer height works well for the engravings
• For two-color prints, do a filament change at the layer where the inlay starts (= body thickness − inlay depth)
• Increase the QR error correction level if you plan to print very small

Built on top of the excellent scadqr library by Darwin Schuppan (MIT-licensed), which is bundled inside the file.