Standard message trailer

The FIX 4.4 Standard Message Trailer is a set of fields that appears at the end of every FIX message.

It contains the three-digit character representation of the Checksum value to ensure the integrity and validity of the message.

Tag	Name	Type	Required	Description
10	`CheckSum`	`String`	yes	Three-character value representing the checksum of the entire message, including all header, body, and trailer fields. The checksum is calculated by summing the ASCII values of all characters in the message and taking the result modulo 256. Must always be last field in message.