GDTI-96
Global Document Type Identifier (96-bit)
urn:epc:id:gdtiWhat is GDTI-96?
Identifies a document - a certificate, a permit, a ticket, a licence, a tax receipt. The GDTI encodes a document type and a serial number so each individual document can be tracked.
Used for: Land title certificates, insurance policies, event tickets, government permits, tax documents.
Field layout
The first 8 bits are always the header (0x2C = 44 decimal), which identifies this as GDTI-96. The partition field determines how bits are divided between the company prefix and the following reference field - see the partition table below.
Defined in GS1 EPC Tag Data Standard v2.3, Section 7.10 (Global Document Type Identifier), encoding procedure in Section 14.6.8.1.
| Bits | Field | Description |
|---|---|---|
0–7 | Header | 0x2C (44) - identifies this encoding as GDTI-96 |
8–10 | Filter | Currently only value 0 is defined. |
11–13 | Partition | Splits bits between company prefix and document type. |
14–53 | Company Prefix | GS1 Company Prefix of the document issuer. |
54–54 | Document Type | Document type reference. Size varies by partition. |
55–95 | Serial Number | 41-bit numeric serial for this individual document. |
Filter values
The 3-bit filter field does not affect identity - it tells readers what packaging level or category the tag is applied to. The same item with different filter values has the same Pure Identity URI .
Source: GS1 EPC TDS v2.3, Table 10-7.
| Value | Name | Description |
|---|---|---|
0 | All others | Unspecified document type |
1 | Reserved | Not yet assigned |
2 | Reserved | Not yet assigned |
3 | Reserved | Not yet assigned |
4 | Reserved | Not yet assigned |
5 | Reserved | Not yet assigned |
6 | Reserved | Not yet assigned |
7 | Reserved | Not yet assigned |
Partition table
The 3-bit partition value determines how the fixed bit space is divided between the company prefix and the following reference field. GS1 company prefixes vary in length (6–12 digits), so the partition tells the decoder where one field ends and the next begins.
Source: GS1 EPC TDS v2.3, Table 14-29.
| Partition | Prefix bits | Prefix digits | Ref bits | Ref digits |
|---|---|---|---|---|
0 | 40 | 12 | 1 | 0 |
1 | 37 | 11 | 4 | 1 |
2 | 34 | 10 | 7 | 2 |
3 | 30 | 9 | 11 | 3 |
4 | 27 | 8 | 14 | 4 |
5 | 24 | 7 | 17 | 5 |
6 | 20 | 6 | 21 | 6 |
Barcode equivalents
The same identifier carried by GDTI-96 can also be encoded in these barcode symbologies. In many supply chains, items carry both an RFID tag and a barcode so that they can be read by either technology.
| Barcode | How it relates |
|---|---|
| GS1-128 | AI (253) encodes the GDTI including serial component |
| GS1 DataMatrix | AI (253) in a 2D symbol for document tracking |
Related schemes
Source
GS1 EPC Tag Data Standard, Release 2.3, Ratified October 2025 - see Section 7.10 (Global Document Type Identifier) and Section 14.6.8.1 for the encoding procedure . Read the EPC encoding guide for a full worked example of decoding hex to URI.