EMV Tag Dictionary
Every EMV data object tag with its published name, searchable by tag number or by name. Useful reference when reading a chip transaction dump or implementing a terminal.
How this tool works
The EMV specifications register every tag a chip application may carry, with its name, its format and its length. This tool is that register, searchable by tag number or by name, so you can look up what a tag means and what it holds without holding the specification to hand.
It is useful in two directions. Given a tag from a record you have captured, it tells you what the field is. Given a field you want, it tells you the tag to look for. The format matters as much as the name: a tag can be a numeric value, a character string, a binary blob, a nested structure or a proprietary format, and the format tells you how to interpret the bytes rather than printing them as text.
Selected tags
| Tag | Name | Format |
|---|---|---|
| 4F | Application Identifier (AID) | AID |
| 50 | Application Label | Text |
| 57 | Track 2 Equivalent Data | Binary |
| 5A | Application PAN | Binary |
| 5F24 | Expiration Date | Binary |
| 5F28 | Issuer Country Code | Binary |
| 9F26 | Application Cryptogram | Binary |
| 9F27 | Cryptogram Information Data | Binary |
A binary tag has a fixed length and a bit layout rather than a character encoding, so it must be decoded before it can be read.
When to use it
- Look up what a tag in a captured record means
- Find the tag number for a field you are looking for
- Check the format and length of a tag before decoding it
- Learn the tag structure of a chip application
Frequently asked questions
What is an EMV tag?
A one, two or four byte identifier for a data element in a chip record, registered in the EMVCo specifications. It says what the data is; the length and the format say how to read it.
What is the difference between a two byte and a four byte tag?
A two byte tag is a registered, standardised field. A four byte tag is either a proprietary field or a reserved combination, and the leading byte says which.
What does a binary format tag mean?
That the value is a bit field rather than text, with a fixed layout defined in the specifications. It has to be decoded bit by bit rather than printed as characters.
Where do I find the tag for the expiry date?
5F24, as a binary value in YYMMDD form, with 00 meaning no expiry. The PAN is 5A and the track 2 equivalent data is 57.
Do the tags differ between brands?
The core set does not. The specifications are common, and proprietary tags are used for things a specific scheme or issuer needs to add.