QR Code Anatomy

Explore the components that make up a QR code symbol.

Finder Pattern

Three identical 7x7 module squares located at the top-left, top-right, and bottom-left corners of every QR code. Each consists of …

A one-module-wide white (light) border that surrounds each of the three finder patterns, separating them from the data region. The …

Two single-module-wide lines of alternating black and white modules — one horizontal along row 6 and one vertical along column …

5x5 module squares placed at regular intervals across the QR code (absent in Version 1). Each has a single dark …

A 15-bit sequence encoding the error correction level (2 bits) and mask pattern (3 bits), protected by a BCH(15,5) error-correcting …

An 18-bit sequence encoding the QR code version number (6 bits) with a Golay(18,6) error-correcting code. Present only in versions …

A single always-dark module at the fixed coordinate (8, 4v+9) where v is the version number. In Version 1, this …

All modules not occupied by function patterns, format/version information, or separators. The data region contains the actual encoded payload (mode …

Reed-Solomon parity codewords interleaved with data codewords in the data region. QR codes use four EC levels: L (7% recovery), …

A mandatory white (light) margin of at least 4 modules surrounding the entire QR code symbol. The quiet zone must …

One of eight predefined XOR patterns applied to the data region during encoding. The encoder evaluates all eight masks and …

Zero-value padding bits added after the last error correction codeword to fill the remaining module positions in the data region. …