Filter Value

What is the filter value?

The filter value is a 3-bit number (0–7) present in most EPC encoding schemes. It tells RFID readers what packaging level the tag is attached to - an individual item, a case, a pallet, or another category - so the reader can quickly decide whether to report the tag or ignore it.

The filter value appears in the Tag URI but not in the Pure Identity URI. It is encoding metadata, not identity. Two tags with different filter values but the same identity fields refer to the same object.

Why it matters

In a warehouse, a reader might see tags on individual bottles, cases of 24, and pallets of 48 cases - all at the same time. The filter value lets the reader's software quickly sort reads by level without having to decode and look up each identity.

A typical use case: a dock door reader is configured to only report pallet-level tags (filter 6 in SGTIN). Individual item tags (filter 1) are ignored, avoiding a flood of irrelevant reads.

Each scheme has its own filter table

Filter values are not universal. The same numeric value means different things in different schemes. For example:

This is why the header byte - which identifies the scheme - must be decoded before the filter value can be interpreted. See each scheme page for its complete filter table:

Filter value in the URI

The filter value sits right after the scheme name in the Tag URI. It is absent from the Pure Identity URI:

Source

GS1 EPC Tag Data Standard, Release 2.3, Section 10 (Filter Values). Each scheme's filter table is listed in a separate table within that section.