# TWIC / CAC Wiegand 58 bit format

Everything you need to understand TWIC / CAC Wiegand 58 bit format

## Card format Overview

A proprietary 58-bit card format used in access control systems, featuring a unique structure composed of 14-bit agency code, 14-bit system code, 20-bit credential code, 4-bit credential series, and 4-bit individual series issue, and 2 parity bits (even and odd), allowing for easy management and avoiding card number duplication for secure, contactless access.

## TWIC / CAC Wiegand 58 bit format format properties

### Agency Code

14 bits (Bits 2-15), range 0-16,383.

### System Code

14 bits (Bits 16-29), range 0-16,383.

### Credential Code

20 bits (Bits 30-49), range 0-1,048,575.

### Credential Series

4 bits (Bits 50-53), range 0-15.

### Individual Series Issue

4 bits (Bits 54-57), range 0-15.

### Even parity

Even Parity for Even parity over bits 1-28.

### Odd parity

Odd Parity for Odd parity over bits 29-57.

### Generate examples

Put in the values for this card format, we'll generate the results in a few different formats.

### Here's your example

| Format    | Value                                                   |
|-----------|---------------------------------------------------------|
| Hex       | 3200C8000C9FE<br>Copy                                    |
| Decimal   | 879662989363710<br>Copy                                  |
| Binary    | 0000000011001000000000110010000000000000001100100111111110<br>Copy |