QR Code ISO 18004 Standard
Definition: ISO/IEC 18004 is the international standard that defines QR code symbology — its encoding, structure, error correction, and format specifications.
ISO/IEC 18004 governs everything about QR codes: the 40 versions, 4 encoding modes, 4 error correction levels, 8 mask patterns, and the physical structure including finder patterns, timing patterns, and alignment patterns. First published in 2000 and updated in 2006 and 2015. Compliance with this standard ensures that any QR code can be read by any compliant scanner worldwide. The standard is maintained by ISO/IEC JTC 1/SC 31.
Key points
- ISO/IEC 18004:2015 current version
- Governs all QR code specifications
- Ensures universal scanner compatibility
- Defines 40 versions and 4 EC levels
- Maintained by ISO/IEC JTC 1/SC 31
- Free patent — open for anyone to use
Frequently asked questions
Is QR code an open standard?
Yes — while ISO 18004 is a paid standard document, the QR code patent is held by Denso Wave who chose not to enforce it. Anyone can create and read QR codes freely.
Why does the standard matter?
It ensures interoperability. A QR code generated in Japan scans correctly on a phone in Brazil because both follow ISO 18004.
Are there competing 2D code standards?
Yes — Data Matrix (ISO 16022), Aztec Code (ISO 24778), and PDF417 (ISO 15438). QR codes dominate consumer applications.
Related terms
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