Message
Include the country code for anything that might be scanned abroad.
Uses the sms:number?body= form, which both iOS and Android accept. Some older Android builds ignore the prefilled text and open an empty message, so test on a real device before printing.
Preview
Enter a phone number and the QR code will appear here.
Held in the hand. Keep the content short, because a long URL makes this too dense.
Rendered at 300 dpi for the physical size, at 85 × 55 mm. The destination is printed in small type beneath the code so a failed scan is not a dead end.
Kept in this browser so you can reopen and edit it later. Nothing is uploaded.
Design
The blank margin scanners use to find the code's edges. Four is the specified minimum, so the slider does not go lower.