How A Magnetic Stripe Card Reader Works

  • December 14, 2018
  • Blog

Much of our modern world is digitized and coded so that all of our personal information is stored in chips and stripes. Credit and debit cards are perhaps the most common object we use daily that has a magnetic stripe on it, but they’re also used on IDs and keycards. Find out how a magnetic stripe card reader processes your information and better understand how your information is dispersed today.


Coded With Information


Miniscule, iron-based particles make up the stripe on cards. A device that produces a strong magnetic field can magnetize these particles in different directions. The information stored on a card is encoded in the particles. The concept of storing information in a magnetic stripe is similar to how magnetic recording tapes in cassettes or videotapes work. Magnetic stripes can hold an account name and details in the case of credit or debit cards or college IDs and security information in the case of hotel room keycards. The stripe on any of these kinds of cards can typically store up to 60 characters magnetically.


Reading The Cards


Credit card readers or magnetic ID card readers are equipped with devices that can control the magnetized particles in a card’s stripe. That device is a solenoid, which is coil wound into a tightly packed helix. The coil winds around a high-permeability, metallic core. This core produces a strong magnetic field when a current passes through it. When a card is moved over or through a magnetic stripe card reader, it induces a voltage in the coils of the device.


This voltage is amplified so that it can be recorded electronically and read by a computer or a processor installed within a magnetic stripe reader. This final reading is what authenticates transactions made with credit cards and debit cards or users identifying themselves with ID cards. A solenoid is the same device that initially encodes the particles of a magnetic stripe, allowing it to be decoded each time it is run through a similar device.


This technology provides a secure way for users to store personal information and bring it with them wherever they go. While chip readers are becoming more popular and many consumers are even using their smartphones in place of credit cards, the magnetic stripe is a trusty go-to for cards holding sensitive data everywhere.