RFID Card Have Two Different Codes Decimal and Hexadecimal

Question

So, here's the deal: I've scanned this NFC tag with two different devices, and they're giving me different results:

Reading 1: 000005E4FA9D Reader: Promag MF700/MF7

Reading 2: 3108611405 Reader: Normal RFID Reader

Now, the thing is, I'm trying to figure out what's up with this tag. I need to convert this code into a hexadecimal for matching purposes. According to an app called NFC Tools, this tag is supposed to be a "MiFare Classic 1k ISO 14443-3A."

I'm scratching my head wondering why the readings don't match up. Possible different ways to read the data?

I already try:

Scan with both readers, check the Reader try to convert to hexadecimal but dont be the correct value

Answer 1

Common different ways that the Non Unique ID can be read.

Some readers only read the first 4 bytes of a 7 byte ID.

Some reader read all 7 bytes.

Some readers return the ID in the reverse byte order.

A Mifare Classic EV1 1k can also be configured to return it's ID in 4 different ways, one of which includes a random ID or a calculated 4 byte ID from the 7 byte ID (I don't know how this is calculated). Normally all genuine Tags from NXP should start with 04h and a random ID should start with 08h.

But none of these seem to fit your data.

I would use the NXP Taginfo App on an Android of iPhone to look at the Tag ID's to compare to what your 2 readers are giving and do repeated reads to check that the Tag is not set to Random ID.

I don't think there is a way to check which of the 4 different ID modes a Tag is operating in.