Magnetic Key Cards System Types

Magnetic Key Cards System Types


Metal keys are quickly becoming rare as technology improves. In locations such as hotels and office buildings, people are using key cards instead of traditional keys. There are four types of key card systems: holecards, bar code cards, magnetic key cards and radio frequency identification (RFID) cards.

Key card systems are programmed to respond to a particular key card reader, a lock or a set of locks. An individual key card is programmed by a computer with a unique electronic signature. If stolen, magnetic strip cards and RFID cards can have the signatures changed, adding security protection from theft.

Holecards are the earliest type of key card systems. In 1975, inventor Tor Sornes devised a system that would punch a series of 32 holes into a plastic card. The card would correspond to a lock and would open a door when it was inserted into a slot in the door. As technology increased, this key card was left behind because of its coding limitations, the labor involved in production and its fragility.


Bar code cards were the next innovation in key card technology. In this key card system, an individual bar code is created to correspond with a particular lock and is printed on a card. The code is exactly like the bar code found on many products sold in stores, which utilizes an electric scanner. This type lost popularity when magnetic strips became more readily available and because bar codes could be forged and the electronic scanner easily tricked.

Magnetic key card systems are widely used in the hotel industry and in workplace security. This card looks like a credit card with a thin metallic strip on the back. This card is swiped through a scanner like a credit card, and it opens a corresponding door because of the electronic signature on the card. This type of card is much more difficult to forge than holecards and bar codes, providing an added layer of security.

RFID key card systems are a more recent form of technology than holecards, bar code cards or magnetic key cards. RFID cards have a radio sensor chip embedded inside the card. When brought into close proximity of a corresponding reader, the door unlocks. The technology used by this type of card includes microchips and radio technology, so it is considered the most difficult to forge and provides the highest level of security.