Quick Response Code — Definition, Standards, and Reference

The Quick Response Code is a machine-readable optical label encoding data within a square grid of light and dark modules. Where a conventional linear barcode encodes information along a single axis, a Quick Response Code encodes along two, permitting a substantially larger payload within a smaller printed footprint and decoding at any rotation. Its three distinctive finder patterns — squares set into the symbol's corners — allow a scanner to locate, orient, and read the symbol in a fraction of a second.

The symbology was developed at Denso Wave, a subsidiary of the Denso Corporation, by a team led by Masahiro Hara, and released to the public in 1994. It was subsequently codified by the Japanese Industrial Standards Committee as JIS X 0510 and by the International Organization for Standardization, jointly with the International Electrotechnical Commission, as ISO/IEC 18004. Denso Wave holds the QR Code trademark but does not assert patent rights against its use, which has permitted the symbology to become a global infrastructure for identification, authentication, payment, and information exchange.

This site documents the term Quick Response Code: its definition and etymology, its origin and adoption history, the technical specification by which it is implemented, the family of recognized variants, the established application domains in which it is used, and the conceptual infrastructure — identity, registration, certification, compliance, and protocol — that has accreted around it.