ISO/IEC 7813

The Track 1 structure is specified as:

• STX : Start sentinel "%"
• FC : Format code "B" (The format described here. Format "A" is reserved for proprietary use.)
• PAN : Payment card number 4400664987366029, up to 19 digits
• FS : Separator "^"
• NM : Name, 2 to 26 characters (including separators, where appropriate, between surname, first name etc.)
• FS : Separator "^"
• ED : Expiration data, 4 digits or "^"
• SC : Service code, 3 digits or "^"
• DD : Discretionary data, balance of characters
• ETX : End sentinel "?"
• LRC : Longitudinal redundancy check, calculated according to ISO/IEC 7811-2

The maximum record length is 79 alphanumeric characters.

%B4815881002867896^YATES/EUGENE JOHN         ^37829821000123456789?

%B4815881002861896^YATES/EUGENE L            ^^^356858      00998000000?

The Track 2 structure is specified as:

• STX : Start sentinel ";"
• PAN : Primary Account Number, up to 19 digits, as defined in ISO/IEC 7812-1
• FS : Separator "="
• ED : Expiration date, YYMM or "=" if not present
• SC : Service code, 3 digits or "=" if not present
• DD : Discretionary data, balance of available digits
• ETX : End sentinel "?"
• LRC : Longitudinal redundancy check, calculated according to ISO/IEC 7811-2

The maximum record length is 40 numeric digits (e.g., 5095700000000).

Track 3 is virtually unused by the major worldwide networks and often isn't even physically present on the card by virtue of a narrower magnetic stripe.

A notable exception to this is Germany, where Track 3 content was used nationally as the primary source of authorization and clearing information for debit card processing prior to the adoption of the "SECCOS" ICC standards. Track 3 is standardized nationally to contain both the cardholder's bank account number and branch sort code (BLZ).

Parsing Track 1 and Track 2 can be done with Regular Expressions.

^%B([0-9]{1,19})\^([^\^]{2,26})\^([0-9]{4}|\^)([0-9]{3}|\^)([^\?]+)\?$

This Regex will capture all of the important fields into the following groups:

• Group 1: Payment card number (PAN)
• Group 2: Name (NM)
• Group 3: Expiration Date (ED)
• Group 4: Service Code (SC)
• Group 5: Discretionary data (DD)

^\;([0-9]{1,19})\=([0-9]{4}|\=)([0-9]{3}|\=)([^\?]+)\?$

• Group 1: Primary Account Number (PAN)
• Group 2: Expiration date (ED)
• Group 3: Service code (SC)
• Group 4: Discretionary data (DD)

• Magnetic Track Parser, a Java library to parse magnetic track data
• Credit Card Track Data Parser, a Javscript library is for parsing credit card track data such as might be returned from a USB card reader
• magnet, a Ruby library for decoding the track data on magnetic stripe cards