ISO/IEC 7813

ISO/IEC 7813 is an international standard codified by the International Standards Organization and International Electrotechnical Commission that defines properties of financial transaction cards, e.g. ATM or credit cards.

The standard defines:

• physical characteristics, e.g. size, shape, location of magnetic stripe etc.
• magnetic track data structures

Physical characteristics

ISO/IEC 7813 specifies the following physical characteristics of the card, mostly by reference to other standards:

Embossed characters 

by reference to ISO/IEC 7811

Embossing of expiration date 

the format, e.g. MM/YY or MM-YY

Magnetic stripe 

by reference to ISO/IEC 7811

Integrated circuit with contacts 

by reference to ISO/IEC 7816-1

Integrated circuit without contacts 

by reference to ISO/IEC 10536-1, ISO/IEC 14443-1 or ISO/IEC 15693-1, as appropriate

Magnetic tracks

Track 1

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 : Primary Account Number, 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.

Samples

%B6011898748579348^DOE/ JOHN              ^37829821000123456789?

%B6011785948493759^DOE/JOHN L                ^^^0000000      00998000000?

Track 2

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.

Track 3

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.

Programming

Parsing Track 1 and Track 2 can be done with Regular Expressions. Included here is just the Regular Expression for parsing Track 1.

Track 1

^%([A-Z])([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: Format Code
• Group 2: Primary account number (PAN)
• Group 3: Name
• Group 4: Expiration Date
• Group 5: Service Code
• Group 6: Discretionary data