Structured data helps search engines understand what your content actually is, a recipe, a product, an FAQ, a local business, and there are three ways to add it, which is why the json-ld vs microdata question comes up so often. All three formats express the same schema.org vocabulary, so the real decision is about how you write it and maintain it. This guide compares JSON-LD, Microdata and RDFa, explains the trade-offs, and gives you a clear recommendation.
What all three have in common
JSON-LD, Microdata and RDFa are three syntaxes for the same thing: describing your content using the shared schema.org vocabulary so search engines can parse entities and their properties. Whichever you choose, you are declaring types like Article, Product or FAQPage and their properties. When done correctly, structured data can make a page eligible for rich results, the star ratings, FAQs, breadcrumbs and other enhancements that stand out in search. The format changes how the markup is written, not what it can express.
JSON-LD: the recommended standard
JSON-LD (JavaScript Object Notation for Linked Data) keeps your structured data in a single <script type="application/ld+json"> block, usually in the page head, completely separate from the visible HTML. That separation is its superpower: you can add, edit or remove markup without touching your templates or your content, which makes it far easier to maintain and far less likely to break when your design changes. Google explicitly recommends JSON-LD, and it is the format most CMS plugins, tag managers and tools generate.
Microdata: inline in your HTML
Microdata is written directly into your visible HTML using attributes like itemscope, itemtype and itemprop on the elements that contain the data. Because it wraps the actual content, some developers like that the markup and the visible text cannot drift apart. The downside is that it clutters your templates, is fiddly to edit, and tightly couples your structured data to your markup, so a redesign can easily break it. It is fully supported, just harder to maintain at scale.
RDFa: the flexible but complex option
RDFa (Resource Description Framework in Attributes) is also inline, added through attributes such as vocab, typeof and property. It is the most expressive and standards-heavy of the three and can reference multiple vocabularies, but that power comes with complexity. For typical SEO structured data it is overkill, and it shares Microdata’s core drawback of living inside your markup. Few teams reach for RDFa unless they have a specific linked-data requirement.
Side-by-side comparison
| JSON-LD | Microdata | RDFa | |
|---|---|---|---|
| Where it lives | Separate script block | Inline in HTML | Inline in HTML |
| Ease of maintenance | High | Low | Low |
| Couples to markup? | No | Yes | Yes |
| Google’s preference | Recommended | Supported | Supported |
| Complexity | Low | Medium | High |
| Best for | Almost all SEO use | Legacy or content-coupled setups | Advanced linked-data needs |
So which should you use?
For almost every website, the answer is JSON-LD. It is the format Google recommends, the easiest to add and maintain, and the least likely to break when your site changes. Choose Microdata only if you have a specific reason to keep markup coupled to visible content, or an existing implementation you are maintaining. Reach for RDFa only when a genuine linked-data requirement demands it. When in doubt, JSON-LD is the safe, future-proof default.
A quick look at the same markup in each format
Seeing one entity expressed three ways makes the trade-off obvious. Imagine marking up a single article. In JSON-LD, you add one self-contained block in the head: a script that declares "@context": "https://schema.org", "@type": "Article", and properties like headline, author and datePublished as plain key-value pairs, entirely separate from your visible HTML. In Microdata, the same information is scattered across your body markup: an itemscope itemtype on the wrapping element, then an itemprop attribute on each element that holds a value, so your headline, author and date each carry an extra attribute. RDFa looks similar to Microdata but uses typeof and property attributes and can pull in additional vocabularies. The information is identical in all three; only JSON-LD keeps it in one place you can edit without touching the page’s content.
Common structured-data mistakes
Whichever format you pick, the errors that actually cost you rich results tend to be the same few. The biggest is a mismatch between your markup and the visible page: marking up a review rating or price that a user cannot see on the page violates Google’s guidelines and can trigger a manual action. Next is missing required properties, a Product without an offer or a review without a rating simply will not qualify for the enhancement. Invalid syntax is another, and it is especially easy in inline formats where a misplaced attribute quietly breaks the item. Finally, people forget that structured data makes a page eligible for a rich result but never guarantees one; Google decides. Validate every change, keep the markup honest to the page, and include the recommended properties, and you avoid nearly all of it.
Get your JSON-LD right
The most common structured-data problems are not about which format you picked, they are syntax errors and missing required properties. A single misplaced comma can invalidate a whole block, and a schema type with missing recommended fields simply will not earn the rich result. Generate valid markup for any type with our schema markup generator, then paste it into our schema validator to confirm the syntax and required fields before you ship it. Both live alongside the rest of our free SEO tools.
Can you mix formats?
Technically you can place more than one format on a page, but you should not, and definitely not describing the same entity twice. Two conflicting descriptions of the same thing (say, a JSON-LD Product and a Microdata Product with different prices) give search engines contradictory data and can suppress the rich result entirely. If you are migrating an old Microdata implementation to JSON-LD, switch a page fully rather than layering the new on top of the old, and remove the legacy attributes once the JSON-LD is validated. The only reasonable exception is when a plugin or platform injects one format automatically and you add another for a type it does not cover, and even then you want to be sure the two never describe the same entity. As a rule: pick one format, standardize on it across the site, and keep every page’s structured data singular and consistent.
The bigger picture
Structured data does not rank you on its own; it makes your already-relevant pages eligible for richer, more clickable results and helps search engines and AI systems understand your content. Pick JSON-LD, keep it valid, and apply it to the content types that qualify for rich results. SEO Rocket audits your technical setup, finds keyword and content opportunities, and generates publish-ready content on real Ahrefs data. Free plan to start, paid plans from $49/month: app.seorocket.ai.
