QR code STL generator

1. Choose what the code holds: a link, your Wi-Fi details or plain text.
2. Scan the preview with your phone to check it opens the right thing.
3. Pick the size, the colours and a sign, coaster or tag with a hole. Add a caption like “Scan for Wi-Fi” if you like.
4. Download the STL (one piece) or the 3MF with the code and the base as two colours.

The code is made in your browser. Your Wi-Fi password and links are never uploaded.

• Dark squares on a light base. Most phone cameras can't read a light code on a dark background. The tool warns when the colours are too close.
• Big enough squares. Aim for 1.6 mm or more per square with a 0.4 mm nozzle; the panel shows the size. A shorter link needs fewer squares, so the same code width gives bigger ones.
• A clear border. The base keeps a plain margin around the code, which scanners need to find it.
• Matte filament scans better than shiny or silk, which can reflect light into the camera.
• Higher error correction keeps it readable when scratched, dirty or partly covered, at the cost of more, smaller squares.

Print the base in a light colour and change to a dark filament at the top of the base (2 mm): in PrusaSlicer with the + on the layer slider, in Bambu Studio or OrcaSlicer by right-clicking the layer slider, in Cura with the Filament Change post-processing script. With a multi-colour printer, open the 3MF and give the code and the base different filaments.

A Wi-Fi code lets guests join by pointing their camera at it: the camera apps on iPhone and Android offer to connect. Pick the security your router uses (almost always WPA/WPA2/WPA3), and tick “Hidden network” only if your network doesn't show up in lists. If you change your password, print a new code.

Want words instead of a code? Try Text to STL for name tags and signs.