The Differences Between Proximity Cards and Key Fobs

The Differences Between Proximity Cards and Key Fobs

by Josh Murray on June 06, 2022

Proximity cards and access key fobs both serve the same basic purpose: they get you into your building. They are both equipped with access control technology and a code that’s unique to you. However, there are some crucial differences between proximity cards and key fobs you should know about before you make your choice.

Size and Shape

The most obvious differences are visible at a surface level. A prox card or door entry card looks more like an ID, printed in a standard CR80 size comparable to a driver’s license. Meanwhile, a key fob is smaller and thicker, about the size of a poker chip.

The different shapes and sizes allow you to transport the keys differently. The size of a proximity card makes it easy to keep with other similarly-shaped cards, such as IDs or hung from a lanyard. Fobs fit perfectly on a keychain and can be kept with your other, more traditional keys.


A proximity card has plenty of surface area for you to use. Many of AuthorizID’s access cards are printable, so you can use them as a badge ID as well. Print an employee’s name, photo, and any other necessary information on the card for an added security benefit.

Key fobs are more subtle. They’re plain, understated, and serve the same purpose as a proximity card without any flash or fanfare. If you don’t want your employees’ names and identifying info out in the open, a key fob may be the way to go.


As we briefly mentioned, proximity cards can be customized in ways that key fobs can’t. The size and shape of a prox card allow your employees to use their access credential as a photo ID. Does your building use a point of sale system?  Proximity cards can come equipped with a  magnetic strip that can be programed with your POS information.  Do your employees use a barcode scanner to clock in? Print that barcode on on your proximity ID badge for an extra level of convenience.

Don’t discount key fobs on this front, though. For some industries, excess identifying information can do more harm than good. In addition, having an access card hanging around your neck can be a nuisance and can potentially cause a choking hazard in some industries.  On the other hand, RFID key fobs still take care of your basic access control needs.  You can still tailor your employees’ key fobs to open certain doors but not others, and with a sleek grey fob, you’ll do it in style.

When looking into proximity access cards or key fobs, there are more differences between them than meet the eye. However, at the end of the day, they both serve the same purpose. Choose the building access solution that benefits your industry and keeps your employees safe.