Storage capacity for a magnetic swipe card

Question

Any idea regarding the usual storage capacity of a magnetic swipe card ( like the ones that are used in ATM's ) ?

(PS : Tried googling but didn't get anything satisfactory and point on)

Waechter

Answer 1

From http://en.wikipedia.org/wiki/Magnetic_stripe, it appears that the card is composed of three tracks (as previously mentioned by Pax), and Tracks 1 and 3 have a bit density of 210 bits/inch, while Track 2 has a bit density of 75 bits per inch.

If the strip is 3.25" long, then it can theoretically store 1607 bits, with 682 on each of Tracks 1 and 3, and 243 on Track 2.

Bronchitis

Answer 2

ISO 7813 specifies the layouts for track 1 and 2. Track 3 is covered by ISO 4909.

Track 2 is the one commonly used for banking.

See ISO7813 and ISO4909 for details. Sorry, no wikipedia for 4909, you'll have to buy the docs from ISO or your country's standards body.

Achieve