Supported GS1 Application Identifiers

Every Application Identifier (AI) the Closient Digital Link resolver understands — the primary keys it resolves, the qualifier AIs permitted for each, and the data-attribute AIs it reads from the query string. These tables are generated directly from the resolver's own validation code, so they cannot drift from what the resolver actually does.

The resolver accepts the uncompressed GS1 Digital Link URI form — for example /01/{gtin}/10/{lot}/21/{serial} — with data attributes such as ?17={expiry} on the query string. The compressed Digital Link syntax is not yet supported.

Want proof instead of promises? See the daily GS1 conformance report — the official GS1 resolver test suite, run against this resolver every day.

Primary key identifiers

A Digital Link URI always starts with one of these primary key AIs. "Resolves" means the resolver routes the identifier to a live destination (redirect, linkset, or JSON-LD).

All 16 primary key AIs resolve — the resolver routes each to a live destination (redirect, linkset, or JSON-LD). Identifiers that fail GS1 format validation return a structured 400 stating why, rather than failing silently.

Qualifier AIs

Qualifiers follow the primary key in the URI path (e.g. /01/{gtin}/10/{lot}). Per the GS1 Digital Link standard, each primary key permits only specific qualifiers.

Data-attribute AIs

Data attributes ride on the query string (e.g. ?17=261231&10=LOT42). The resolver surfaces these as supplementary information — they never change which product or entity the URI identifies.