What the standard covers
ISO/IEC 18004 specifies everything needed to make and read a QR code: the finder, timing and alignment patterns, the 40 versions, the encoding modes, the four error correction levels, the mask patterns and the format and version information. It also gives a reference decoding algorithm and guidance on print quality.
The standard is published jointly by ISO and IEC through their joint technical committee on information technology. Its full text is sold through the ISO catalogue and national standards bodies.
Editions
The first edition appeared in 2000, following the AIM International standard of 1997 and the Japanese standard JIS X 0510 of 1999. The 2006 edition added Micro QR code.
A third edition followed in 2015 and a fourth in 2024. The core symbol structure has stayed stable across editions, so codes made to earlier editions generally still scan with current readers.
- 2000: first edition
- 2006: second edition, adds Micro QR code
- 2015: third edition
- 2024: fourth edition published
Related standards
Other QR-family formats have their own standards. The rectangular rMQR code was published separately as ISO/IEC 23941 in 2022. Print quality testing for 2D symbols in general is covered by ISO/IEC 15415.