data-vocabulary.org markup: deprecated and ignored by Google

What it means

This page references data-vocabulary.org in a structured-data block — either as an @context value in JSON-LD or via itemtype attributes in Microdata. Google retired this vocabulary from rich-result eligibility and no longer processes it for any search feature. The markup exists in the HTML but produces no benefit.

Why it matters

data-vocabulary.org was Google's own pre-schema.org vocabulary. When schema.org launched in 2011 as a cross-engine standard, Google migrated its rich-result systems to schema.org exclusively and deprecated data-vocabulary.org. The practical implications: breadcrumb markup using it produces no breadcrumb trail, review markup produces no star ratings, and Google does not warn about it in Search Console the way it warns about invalid schema.org markup — the pages silently receive no rich-result treatment. Old WordPress themes from 2011-2015 shipped this Microdata baked into templates, so sites that have not updated their theme in a decade are the most common source. It is a missed opportunity, not active damage, hence a warning.

How to fix it

1. Search your HTML templates and theme files for data-vocabulary.org to find every location.
2. Choose a replacement format — JSON-LD is Google's preferred format and easiest to manage separately from HTML.
3. Replace each type with its schema.org equivalent; the most common mapping is data-vocabulary.org/Breadcrumb -> schema.org/BreadcrumbList.
4. Remove the old Microdata itemscope/itemtype/itemprop attributes if migrating to JSON-LD.
5. Validate the new markup in Google's Rich Results Test.

When it's not a problem

There is no scenario where keeping data-vocabulary.org markup is preferable to migrating. If the site is being sunset or the page is excluded from indexing via noindex, fixing it is low priority — but for any actively indexed page, migration to schema.org is the correct action.

How common is it?

28 audited sites in our corpus currently show this issue. The breakdowns below show which platforms, gatekeepers, verticals and countries are most exposed.