The Standard 26 Bit Format

(c) HID Corporation - Technical Support Department


Tech Tip # 5


The Standard 26-bit Format is an open format.  It is a widely used industry standard, and is available from many sources.  Almost all access control systems accept the Standard 26-bit Format.

There are 256 possible facility codes.  There can be up to 65,535 card ID numbers per facility code.  The total number of cards that can use the entire range without duplication is 16,711,425.  There are no restrictions on the use of this format.  It is not tracked by HID, and there are duplicate cards in use.

The standard 26 bit Wiegand format is H10301.  It is binary encoded data.  The format consists of 2 parity bits, 8 bit facility code and 16 bit card number fields.  The format is shown below.

PAAAAAAAABBBBBBBBBBBBBBBBP
EXXXXXXXXXXXX
             XXXXXXXXXXXXO

where:

P = Parity                                                                      O = Odd Parity

A = Facility code, range = 0 to 255                                  E = Even Parity

B = Card Number, range = 0 to 65,535                              X = Parity mask