You cannot read a passive 125 KHz Tag with a NFC reader, because as you have already guessed, they operate on different frequencies. There are passive RFID cards operating on 13.56 MHz, however, and these will read just fine on a NFC-enabled phone.

RFID is useful for sensing and identifying tagged people and objects for access control, automation, and a whole range of different applications. This basic RFID tag works in the 125kHz RF range and comes with a unique 32-bit ID. It is not re-programmable.

NFC enabled phones can ONLY read NFC and passive high frequency RFID (HF-RFID). These must be read at an extremely close range, typically a few centimeters. For longer range or any other type of RFID/active RFID, you must use an external reader for handling them with mobile devices.

There are a variety of RFID tags on the market today, differentiated by frequency range (low, high and ultra-high). Each RFID type can be either active (powered), passive (un-powered) or semi-passive (battery-assisted).

The EM4100 (previously named H4100) is a CMOS integrated circuit for use in electronic Read Only RF Transponders. The EM4100 has several metal options which are used to define the code type and data rate. Data rates of 64, 32 and 16 periods of carrier frequency per data bit are available.

Make sure this fits by entering your model number. RFID Reader read both 125KHz 1326 family ISO Prox whole family cards & EM ID EM4100 cards together, HID USB device no driver request 125KHz RFID reader supports EM4100 ID cards and also 1326 1346 1386 ISO Prox card, H10301 H10304 format etc.

Proximity card reader sends 125KHz proximity card 1326 family card number in 40 type formats or in raw wiegand bit data format, from 24 bit to 80 bits data, easy for understanding 1326 family card type Card reader only, simulate keyboard input, works in Linux Andriod Windows MacOS, Writer ASIN is B07XJZ1J7B; 1326 Format Card ASIN is:B07QXLH7L3

This Grove-125KHz RFID Reader is a module used to read uem4100 RFID card information with two output formats: Uart and Wiegand. It has a sensitivity with maximum 7cm sensing distance. There is also the electronic brick version of this module. It can help you with project like internet of thing and access control system.

Low frequency bands (125 kHz-400 kHz) were tradi- tionally used in RFID applications. This was because of the availability of silicon devices. Typical carrier frequency (reader’s transmitting frequency) in today’s applications range from 125 kHz-2.4 GHz.