Schema Markup Validator
Paste JSON-LD — or a whole page's HTML — to find syntax errors with line numbers, see every schema.org item it describes, and check common types such as Organization, Product, Article, FAQPage and BreadcrumbList for missing or malformed properties.
How to use the Schema Markup Validator
Paste your markup
Raw JSON-LD, one or more script blocks, or an entire page's HTML.
Fix syntax errors first
Invalid JSON can't be read at all. The error shows the line and column.
Review each item
Every @type is listed with its properties in a tree, including items inside @graph.
Work through the checks
Missing key properties and malformed values are listed per item.
What it checks
- JSON syntax
- Parse errors with line and column, including common causes such as trailing commas and smart quotes.
- Context
- @context present and pointing to schema.org.
- Types
- Every @type found, including nested items and @graph arrays.
- Key properties
- Commonly required or recommended properties for about 25 frequently used types, such as Organization, Product, Offer, Article, BreadcrumbList, FAQPage and Event.
- Value formats
- Absolute URLs, ISO 8601 dates, numeric prices, three-letter currency codes and rating values within their declared range.
- Other formats
- Microdata and RDFa are detected and noted, but only JSON-LD is validated.
Interpreting the results
The summary shows how many JSON-LD blocks were found, how many parsed, and how many items and types they contain. Each item then gets its own panel with a property tree and a list of findings: errors (invalid JSON, missing @type, malformed values) and warnings (properties that are commonly required or recommended for that type but absent).
This is not an official search engine test. It checks syntax and common requirements, which catches most mistakes; eligibility for rich results depends on each search engine's current rules and on the page itself. Use the search engines' own testing tools for a final check.
Detected marks facts read directly from what you provided. Guidance marks general recommendations based on those facts — rules of thumb, not guarantees or search engine requirements.
Practical guidance
Structured data should describe what's visibly on the page — nothing more. Marking up reviews that aren't shown, prices that don't match, or FAQs that aren't on the page can breach search engines' guidelines. The validator can't judge that, so compare each item with the visible content yourself.
A realistic example: a product page's JSON-LD fails to parse because a description contains an unescaped double quote copied from the CMS. Nothing on the page is being read as structured data at all until that one character is escaped. The error message points at the exact line.
Good markup helps search engines understand a page, but it doesn't replace the fundamentals: indexable pages, clear content and relevant links. For a full live review of a page including its JSON-LD, use the SEO Page Analyzer. Our guide What makes a quality backlink? covers the links side, and our PBN backlinks page explains how we choose where links go.
Limitations
- It isn't an official rich-results test and doesn't guarantee eligibility for any search feature.
- Property checks cover common types only; other valid schema.org types are parsed and shown but checked just for general format.
- Microdata and RDFa are detected but not validated.
- It can't check whether the markup matches the visible page content.
Frequently asked questions
What's the difference between required and recommended properties?
Search engines document some properties as required for a rich result and others as recommended. Missing recommended properties doesn't make markup invalid.
Why does my JSON fail to parse?
The usual causes are trailing commas, unescaped quotes inside strings, smart quotes pasted from a word processor, or a missing closing brace.
Can I paste a whole page?
Yes. All application/ld+json script blocks are extracted and validated.
Is my markup uploaded?
No. It's parsed in your browser.
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