26bit

26bit (26-bit) is a term used in several technical contexts to denote data streams or values that are 26 bits long. The most widely known usage is in access-control technology, where “Wiegand 26” is a standard format for encoding an identifier on physical access cards and the readers that process them. In this context, 26-bit schemes are part of legacy and some modern systems, particularly those produced by manufacturers working with the Wiegand interface.

Wiegand 26-bit format transmits a total of 26 bits per card read. The typical payload encodes an 8-bit facility code and a 16-bit card number, representing the issuer and the unique card identifier. Two parity bits provide basic error detection for the data stream. In practice, many vendors implement 26-bit Wiegand with variations in bit order and parity style, but the 8/16 data payload is a common baseline. The format is widely associated with access-control deployments and is still encountered in HID Prox and other legacy card systems, as well as some newer readers that maintain compatibility with older infrastructure.

Outside of access control, 26-bit encodings occur only rarely and are nonstandard. Some manufacturers use 26-bit fields in proprietary protocols or for legacy devices, but there is no universal 26-bit standard beyond Wiegand formats. Modern systems more commonly employ higher-bit-width formats or encrypted data for security and interoperability, which has reduced the use of fixed 26-bit schemes. As a result, “26bit” most often refers to Wiegand 26 rather than a general-purpose data width.