ID Card Encoding

Magnetic stripe cards have been in existence since the early 70's when they were used on paper and film-based ID cards as well as credit cards. Magnetic stripe technology is widely used throughout the world on plastic cards and remains the dominant technology in the United States for transaction processing and access control. Other technologies such as PDF bar codes and smart chip cards for ID cards are now capturing part of the magnetic stripe market since they can hold more information.

Magnetic stripe encoding terms

Coercivity

A technical term used to designate how strong a magnetic field must be to affect data encoded on a magnetic stripe. Coercivity is measured in Oersteds (Oe). Coercivity is the measure of how difficult it is to encode information in a magnetic stripe.

HiCo

Abbreviation for High Coercivity. HiCo magnetic stripes provide the highest level of immunity to damage by stray magnetic fields. They are more difficult to encode than LoCo magnetic stripes because the encoding requires more power. HiCo magnetic stripe cards are slightly more expensive for this reason.

LoCo

Abbreviation for Low Coercivity. Easier to encode and slightly less expensive than HiCo magnetic stripe cards. Selecting which type of magnetic stripe to adopt depends on how the card is to be used. Will the magnetic stripe be used daily, once a month, or just a couple of times a year? The chart below shows some of the applications where magnetic stripes are used and which stripe is common for that application.

The easiest way to determine visually if a stripe on a card is HiCo or LoCo is by the color. HiCo stripes are black and LoCo stripes are a lighter brown. Magnetic stripe readers are "blind" as to whether a stripe is HiCo or LoCo and are designed to read both. Another term often used is Stripe-up and Stripe-down. Stripe-up means the magnetic stripe is on the front of the card and Stripe-down means the magnetic stripe is on the back of the card.

This information is important when ordering a printer since the magnetic encoder must be installed differently for Stripe-up and Stripe-down models at the factory. The most common is Stripe-down. All major ID card printer manufacturers follow the ISO standard for encoding, but can be changed via the Windows driver to enable proprietary encoding. Proprietary encoding offers greater security and most readers can also be easily reprogrammed to read custom encoding.