Comparison

    JSON-LD vs. Microdata vs. RDFa: Which Syntax Should You Choose?

    Three syntaxes, one purpose: making your content understandable for search engines. But there are significant differences in implementation, maintenance and Google's preference.

    March 25, 2026 10 min read AI Schema Team
    JSON-LD vs. Microdata vs. RDFa: Which Syntax Should You Choose?

    When implementing schema markup, you need to choose between three syntaxes: JSON-LD, Microdata and RDFa. All three can communicate structured data to search engines, but they do it in fundamentally different ways — and Google has a clear favorite.

    Google officially recommends JSON-LD as the preferred syntax for structured data. Over 90% of new schema implementations use JSON-LD in 2026 — from FAQ blocks to advanced formats that make content readable for modern AI agents.

    JSON-LD

    JavaScript Object Notation for Linked Data. Placed as a standalone <script> tag in the page's <head> or <body>, separate from HTML content.

    Advantages

    Separated from HTML — easier to maintain
    Recommended by Google
    Can be generated dynamically with JavaScript
    No changes to existing HTML
    Easier to validate and debug

    Disadvantages

    Data can theoretically deviate from visible content
    Requires separate maintenance on content changes

    Microdata

    HTML attributes (itemscope, itemtype, itemprop) added directly to existing HTML elements.

    Advantages

    Data directly tied to visible content
    Built into HTML — cannot deviate

    Disadvantages

    Mixes markup with content — hard to maintain
    Requires HTML structure changes
    Difficult to generate dynamically
    Complex nesting syntax
    Limited tool support

    RDFa

    Resource Description Framework in Attributes. Similar to Microdata but based on the RDF standard with attributes like vocab, typeof and property.

    Advantages

    Supports multiple vocabularies simultaneously
    Part of W3C standard
    More expressive than Microdata

    Disadvantages

    Most complex syntax
    Low adoption — limited community support
    Mixes markup with content
    Redundant for most use cases

    Feature comparison

    FeatureJSON-LDMicrodataRDFa
    Google recommended
    Separated from HTML
    Dynamic generation
    Easy maintenance
    Direct content binding
    Multiple vocabularies
    Rich Results support
    Widespread adoption (2026)

    Why Google recommends JSON-LD

    Google has explicitly declared JSON-LD as the preferred syntax for several reasons:

    • Separation of concerns — JSON-LD separates structured data from HTML, making it easier to maintain both independently.
    • Consistency — Since JSON-LD doesn't depend on HTML structure, there's less risk of markup breaking on design changes.
    • Scalability — JSON-LD can be automatically generated by schema markup generators without touching the existing website.
    • Validation — JSON-LD is easier to test and validate with automated tools.

    When to choose what?

    • JSON-LD (99% of cases) — Choose JSON-LD as default. It's future-proof, maintainable and has full Google support. Ideal for Rich Results, e-commerce and all other use cases.
    • Microdata (legacy) — Only relevant if you already have Microdata implemented and working. Migrate to JSON-LD at next redesign.
    • RDFa (niche) — Only relevant for academic or semantic web projects requiring multiple vocabularies.

    Ready for JSON-LD?

    AI Schema Generator automatically generates optimal JSON-LD markup for your website — with full validation and quality assurance.