This factor checks whether the page’s body HTML contains the Microformats2 u-identifier property, which marks a stable identifier URL for an item. RankGear returns 1 when it finds the class and 0 when it does not — it is a presence signal, not a check of the URL’s value or its parent item.
| Factor ID | RG-SCF-021 |
|---|---|
| Family | Structured Data — MicroFormat |
| Measurement | Binary presence (0 / 1) |
| Measured zone | Body HTML without scripts |
What it measures
This factor detects the u-identifier Microformats2 URL identifier property. In the Microformats2 vocabulary, u-* properties carry URL values, and u-identifier is used to express a stable, canonical identifier URL for the item being marked up. The factor records only whether that property is present in the rendered body markup.
How RankGear measures it
RankGear returns 1 when a case-insensitive scan of the body HTML (scripts excluded) finds the exact sequence class="u-identifier". If that sequence is not present, the factor returns 0. It is a literal string match on the class attribute, so the property must appear as a single, exactly formatted class.
What RankGear looks for
<a class="u-identifier" href="https://example.com/id/12345">#12345</a>| Value | Meaning |
|---|---|
| 1 | The exact class class="u-identifier" was found in the body HTML. |
| 0 | The class was not found (absent, misspelled, or combined with other classes in the attribute). |
How to optimize it
Use u-identifier for a stable, accurate identifier URL when the applicable MicroFormat vocabulary calls for it. Treat this as an observation about your markup rather than a target to chase: add the property only where a genuine item and identifier exist. Because the match is exact, keep it as a single, correctly spelled class so the scan resolves cleanly.
Important considerations
- Exact single-class formatting is required — the scan matches
class="u-identifier"as a literal string, so combined or misspelled class attributes will not register. - The URL value itself is not validated; the factor confirms only that the property is present, not that the identifier resolves or is correct.
- A parent MicroFormat item is not confirmed — the presence of the property does not verify that it sits inside a valid enclosing item.
- Do not create artificial identifiers for this factor. Add
u-identifieronly where a real identifier URL applies. - This is a correlation-based prioritization signal within a measured result set, not a guarantee of ranking. Presence of the property does not by itself cause a page to rank.
Related factors
Part of the Factors reference · how RankGear measures · glossary.