FAQ : technical issues
What is the read range of a contactless card?
Contactless Cards (like access badges, transportation cards, payment cards and other NFC devices) are based on RFID High Frequency (HF) technologies working at 13,56MHz. The coupling between the reader and the card is based on the magnetic field and the protocol is based on ISO/IEC 14443 standard.
The “typical” read distance for a such contactless cards is claimed to be no more than 10 cm. This is based on the fact that:
• A standard ISO 14443 contactless reader is not build to radiate more than 7,5A/m
• Applications require a “wilful act” from the card holder (waving the card in from of a payment terminal)
However, this does not take into account two other factors:
• 13.56 MHz is also used by other protocols (e.g. ISO/IEC 15693 and NFC devices). The reader’s antenna form factor is such that magnetic field is radiated in a greater volume implying a greater reading distance (read ranges for 15963 RFID tags could be up to 1 metre because those RFID chips require less power to be activated than 14443 chips).
• Illegal reading activities ignore the radio regulations so that radiated magnetic fields could much greater than 7,5A/m.
There have been a number of recorded examples of contactless cards being read with standard equipment well beyond the 10 cm claimed.