Schema Markup Validator
Updated September 2026
Check JSON-LD schema markup for valid JSON syntax and the presence of @context and @type. Free online schema markup checker — paste raw JSON-LD or full HTML.
Diagnosing web and network issues quickly is critical for site owners, developers, and SEO professionals. The Schema Markup Validator delivers actionable data in seconds.
Check JSON-LD schema markup for valid JSON syntax and the presence of @context and @type. Free online schema markup checker — paste raw JSON-LD or full HTML. Results are immediate — no waiting, no loading screens, no account required.
Who uses the Schema Markup Validator?
- Developers doing a quick JSON syntax check on JSON-LD before deploying it to production.
- SEO engineers spot-checking that @context and @type are present before a deeper manual schema.org review.
- Content managers reviewing what properties are actually set in existing FAQ or HowTo schema markup.
Common uses and search terms
The Schema Markup Validator is frequently used for: schema markup, structured data, json-ld, rich results. Whether you need a quick result or are working through a longer project, the tool handles all common variations without any configuration.
Why use Allio Tools's Schema Markup Validator?
Everything runs locally in your browser. No data is sent to a server, logged, or stored anywhere. The tool is completely free with no usage limits, no premium tiers, and no account required. Available in 11 languages and optimised for all screen sizes, the Schema Markup Validator works on desktop, tablet, and mobile with no app download needed.
See also:IP Address Lookup · Website Speed Test · DNS Lookup
How the Schema Markup Validator works
Paste your JSON-LD schema markup directly, or paste full HTML containing a <script type="application/ld+json"> tag — the tool extracts the JSON-LD automatically either way.
Click Validate Schema to check for valid JSON syntax and confirm each schema object has @context and @type.
View the stats line for a quick count of schemas found and any missing-field issues.
Scroll down to see every property of each schema laid out in a table for manual review against schema.org's requirements.
Tips & tricks
- Validation is limited to JSON syntax plus a check that @context and @type exist — it does not check type-specific required fields (e.g. FAQPage needing mainEntity, or Product needing offers) or catch wrong value types like a string where a number is expected.
- There's no built-in link to Google's Rich Results Test — after fixing what this tool flags, paste your markup there separately to test actual rich-result eligibility.
- Paste either raw JSON-LD or full page HTML containing a