QR code · 16
QR structured append
Splitting one payload across up to sixteen linked symbols.
Key facts
| Maximum symbols | 16 |
|---|---|
| Header | 4-bit index, 4-bit total, 8-bit parity |
| Requires | Scanner support for structured append |
| Use case | Very large payloads or constrained print areas |
| Parity | XOR of all input bytes |
How the parts find each other
Each symbol starts with a structured-append header: its position, the total number of symbols and a parity byte computed from the entire payload. A scanner reads the parts in any order and uses the header to reconstruct the sequence.
Why it is rarely used
Most phone scanners do not join structured-append sequences, and a single dense symbol is simpler to print and scan. The feature is useful for industrial labels and for payloads that exceed single-symbol capacity, not for ordinary marketing codes.
Frequently asked questions
Will a phone join two QR codes automatically?
Usually not. Consumer scanner apps tend to treat each symbol as a separate result.
What is the parity byte for?
It prevents mixing parts from two different payloads that happen to be scanned together.
Is structured append the same as a multi-part barcode?
Conceptually similar, but the QR mechanism is defined by the standard and travels inside each symbol.