What is structured data for SEO? 6 checks before you invest

A plugin warning or an agency proposal mentions schema markup, and now you wonder whether it deserves budget. The question 'what is structured data for SEO?' has a short answer. It is a standardized way of labelling what a page contains, so search engines read facts instead of guessing. This guide covers what it can and cannot do, plus six checks to make before you spend anything.

What structured data tells a search engine

Google's introduction to structured data markup describes it as a standardized format for providing information about a page and classifying its content. On a recipe page, for example, it labels the ingredients, the cooking time and the calories. Search engines then read those details directly instead of inferring them. Most of the vocabulary comes from Schema.org, a community project founded by Google, Microsoft, Yahoo and Yandex.

Think of it as a label on a box. The text on your page speaks to people, while the markup speaks to machines. Because the two must agree, you never mark up details a visitor cannot see. Google also warns against creating blank pages that exist only to hold markup.

Schema.org reports that over 45 million web domains use its vocabulary, with more than 450 billion objects as of 2024. Adoption is broad, but Google advises relying on its own documentation for Google Search behavior. Schema.org contains many attributes that Google Search does not require, so a long markup file does not mean a better one.

Which format to ask for

Google supports three formats: JSON-LD, Microdata and RDFa. All three work equally well when the markup is valid, but Google recommends JSON-LD for most sites. It sits in a separate script block rather than inside your visible text, so it is easier to maintain. Google can also read it when JavaScript or a content management system injects it, which matters for headless storefronts.

What the evidence shows, and what it does not

Google's documentation lists several case studies. Rotten Tomatoes measured a 25% higher click-through rate on pages with structured data than on pages without it. Nestlé measured an 82% higher click-through rate for pages that appear as rich results. The Food Network also converted 80% of its pages to enable search features and saw a 35% increase in visits.

Read those figures with care, because they are publisher-reported results from large brands with many similar pages. Google presents them as case studies, not as typical outcomes. None of them promises a higher ranking. The markup makes a page eligible for a richer appearance, so the realistic gain is a more attractive listing rather than a better position.

Which markup types fit a business website

Google's gallery of supported features is long, and most of it will not apply to you. A consultancy, a shop and a publisher need different things. Start from your page types, because that keeps the scope small and the maintenance realistic.

Markup type	What Google says it covers	Typically relevant for
Organization	Logo, legal name, address, contact details and company identifiers	Every company site
Local business	Opening hours, ratings, directions and booking actions in the knowledge panel	Businesses with a physical location
Product	Price, availability and review ratings	Online shops
Breadcrumb	The page's position in the site hierarchy	Sites with categories
Article	News, sports or blog articles with titles and larger images	Blogs and publishers
Software app	Rating, description and a link to the app	Software products

Rules differ by type. You must include all required properties for a page to qualify for enhanced display, and adding recommended ones can improve the odds. Google is clear on the trade-off, though: fewer complete and accurate properties beat many incomplete or badly formed ones.

Six checks before you invest

That is what structured data for SEO looks like as a business decision rather than a technical exercise. Run these six checks with whoever builds or maintains your site.

Check six deserves extra weight. A redesign can drop markup unnoticed, so add a validation step to every relaunch. Our ecommerce SEO checklist for small online stores and the guide to category page SEO show where markup fits among other fixes.

How to measure whether it paid off

Google suggests a before and after test on a few pages. Choose pages without structured data that have several months of Search Console history. Pick stable, popular pages that seasonal swings will not distort. Add the markup, confirm Google found it with the URL Inspection tool, then record performance for a few months in the Performance report, filtered by URL. Google admits the comparison is tricky, since page views vary for many reasons.

For a second opinion on validity, Chrome's Lighthouse includes a structured data validity audit. Also watch how rich results change your listing on the search results page, because the visible change is the outcome you are paying for.

Doing it yourself or handing it off

If your site runs on a content management system, Google notes that you can often add structured data through plugins or settings. That usually covers basics such as Organization and Article. Shops, multi-language sites and headless builds tend to need more custom work, because the markup must draw from live product data.

A sensible split is to handle simple site-wide types yourself and hand off anything generated from templates or catalogues. If you want support, the Xerx SEO Care and SEO growth service covers technical SEO alongside content. Costs and suitability vary by site, so ask any provider which types they would add, to which templates, and how they will validate and monitor them.

For background on why shared vocabularies exist, the W3C Library Linked Data group's SEO use case discusses designing sites around Linked Data principles. Start small: one Organization block, one template, one before and after test. Then decide whether to go further.

Action steps

1. List your page types: Write down which templates your site uses, such as home page, service page, product page and blog post, and which markup type each could carry.
2. Start with Organization: Add Organization markup site-wide first, since it applies to every company and is the simplest to keep accurate.
3. Confirm the data exists: Check that each required property, such as price or opening hours, already exists in your catalogue or site settings.
4. Validate before and after launch: Test with the Rich Results Test before release, then watch the rich result status reports in Search Console.
5. Run a before and after test: Pick a few stable pages, add markup, and compare Search Console performance over several months.

Frequently asked questions

Is structured data a ranking factor?

Google describes structured data as a way to help it understand a page and make the page eligible for rich results. Its documentation does not promise higher rankings, so treat any such claim with caution and measure the effect on your own pages.

Which structured data format should I use?

Google supports JSON-LD, Microdata and RDFa, and says all three are fine when the markup is valid. It recommends JSON-LD in most cases because it is easier to implement and maintain.

Does valid markup guarantee rich results?

No. Valid markup with all required properties makes a page eligible for enhanced display, but you also need to follow Google's general and feature-specific guidelines. Google decides whether to show a rich result.

How long before I see a result?

Google suggests recording performance for a few months in the Search Console Performance report, filtered by URL, and comparing it with similar pages that have no markup.

Can I add markup for information that is not on the page?

No. Google says not to add structured data about information that visitors cannot see, even if it is accurate, and not to create empty pages just to hold markup.