# iCLASS truncated CSN 56bit

Everything you need to understand iCLASS truncated CSN 56bit

## Card format Overview

A proprietary 56-bit card format used in access control systems, featuring a unique structure composed of 56-bit card number, allowing for easy management and avoiding card number duplication for secure, contactless access.

## iCLASS truncated CSN 56bit format properties

### Card Number

56 bits. A unique serial number (0-72,057,594,037,927,935) for each card within that facility code.

### 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 | 64<br>Copy |
| Decimal | 100<br>Copy |
| Binary | 00000000000000000000000000000000000000000000000001100100<br>Copy |

## The API that turns phones into key fobs.