The CR80 is the most common card format used in ID cards and credit cards. It ensures that the card will fit in wallets.
54 mm x 86 (85.6) mm
Varies per printing technique
1,5 mm - 3 mm
3 mm
2 cm x 2 cm
Your code should be as high contrast as possible. A minimum contrast ratio of 4:1 is required to ensure the code is readable by most QR code scanners.