Proximity Cards
Proximity cards are contactless cards read when held near a reader. The term usually means 125 kHz low-frequency cards (such as EM-type ID cards) that carry a number used for door access and attendance; it is also used loosely for 13.56 MHz contactless smart cards.
125 kHz Proximity vs 13.56 MHz Smart Cards
| 125 kHz proximity (ID) cards | Carry a fixed number; simple and low cost; widely used for basic access and attendance. |
|---|---|
| 13.56 MHz smart cards (e.g. MIFARE) | Have memory and, in many variants, cryptography; used for access, cashless payment, ID and multi-application systems. |
Basic 125 kHz ID cards only carry a number and can be copied more easily than cryptographic smart cards. For new projects that need stronger security or cashless use, 13.56 MHz cards such as MIFARE DESFire are usually the better choice.
How a Proximity Card Works
The reader emits a field that powers the card’s chip through its coil; the card then sends its number back to the reader, which passes it to the controller or software. No battery is needed in the card.
Frequently Asked Questions
It's a generic name for contactless integrated circuit devices used for security access or payment systems — either older 125 kHz devices or newer 13.56 MHz contactless RFID cards, commonly called contactless smartcards.
Modern proximity cards follow the ISO 14443 standard, with the related ISO 15693 (Vicinity Card) standard covering longer-range variants.
The card contains an IC, capacitor and coil wired as an LC circuit. The reader's field excites the coil and charges the capacitor, which powers the IC to transmit the card's number back to the reader — with no battery needed on the card.
A 125 kHz proximity card typically only carries an ID number. A smart card has memory and, often, cryptographic security, so it can store data and support payments and multiple applications.
They are fine for basic access and attendance, but because they carry only a number they can be copied more easily. Use cryptographic 13.56 MHz cards where security matters.
Yes. Cards can be printed with a logo, photo and details for employee or student ID.