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JSON-LD Validator
Parses JSON-LD structured data, finds every entity, and reports missing required properties and the syntax mistakes that stop it working.
SEO
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No sign-up
Free, unlimited
Paste something on the left to see the result.
In short
JSON-LD Validator is a free online tool on inputtesthub.com that parses JSON-LD structured data, finds every entity, and reports missing required properties and the syntax mistakes that stop it working. It needs no account, no download and no payment, and there is no daily usage limit. Everything is processed inside your own browser, so the data you paste is never uploaded to a server.
How to use the JSON-LD Validator
- Paste your code into the input area.
- Choose the indentation and output options you want.
- Read the formatted result, then copy or download it.
About the JSON-LD Validator
The JSON-LD Validator parses JSON-LD structured data, finds every entity, and reports missing required properties and the syntax mistakes that stop it working. It runs as plain JavaScript inside the page, which means there is no upload step, no queue and no size limit imposed by a server — the only limit is your own device.
What people use it for
- Checking markup before a page is live, when Google's tester cannot reach it.
- Finding which required property is missing from a rich result that never appeared.
- Validating structured data generated by a plugin you do not control.
Details
| Required missing | The rich result is usually dropped entirely |
|---|---|
| @context | Must be schema.org or the block is ignored |
| Curly quotes | A CMS favourite, and fatal to JSON |
| URLs | Must be absolute — there is no page to resolve against |
| price | A bare number; currency goes in priceCurrency |
The maths behind it
This tool uses every object carrying an @type is checked against schema.org's required and recommended properties for that type, and the whole block is checked for the syntax mistakes that stop it parsing at all. Every intermediate value is shown on screen, so the result can be checked by hand.
It validates structure and required properties. It cannot check that your markup matches what a visitor actually sees on the page, and that mismatch is the most common reason structured data is ignored or, in the worst case, treated as spam.
Where this tool stops
The required-property rules cover the types that produce rich results — Article, Product, Recipe, FAQPage, HowTo, Event, LocalBusiness, VideoObject, JobPosting and their common companions. A type outside that list is parsed and reported but not checked against a rule set. Microdata and RDFa are different formats and are not handled.
Frequently asked questions
Why does my structured data not produce a rich result?
Missing a required property is the usual reason, and it fails all-or-nothing rather than degrading — a Product without a name is simply ignored. The second most common cause passes every validator: markup that describes something not visible on the page. Search engines check that the two agree, and a mismatch gets the whole block discounted.
Does this replace Google's Rich Results Test?
No, it comes before it. Google's tester needs the page to be publicly reachable, which is the wrong moment to discover a missing property. Use this while writing the markup, then confirm with Google once the page is live.
Are there any usage caps on the JSON-LD Validator?
There is no cost and no cap. The JSON-LD Validator is not a demo of a paid product, so nothing is held back or watermarked.
Can you see what I put into this utility?
No. The JSON-LD Validator runs entirely in your browser using JavaScript. Because the work happens locally, the utility also keeps working if your connection drops, and closing the tab is all it takes to discard everything.
What formula does the JSON-LD Validator use?
It uses every object carrying an @type is checked against schema.org's required and recommended properties for that type, and the whole block is checked for the syntax mistakes that stop it parsing at all. The full working is printed under the result, so you can follow every step rather than trusting a black box.
Who is the JSON-LD Validator for?
Typical uses: checking markup before a page is live, when Google's tester cannot reach it. Finding which required property is missing from a rich result that never appeared. Validating structured data generated by a plugin you do not control. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
When is the JSON-LD Validator not the right tool?
The required-property rules cover the types that produce rich results — Article, Product, Recipe, FAQPage, HowTo, Event, LocalBusiness, VideoObject, JobPosting and their common companions. A type outside that list is parsed and reported but not checked against a rule set. Microdata and RDFa are different formats and are not handled. Knowing where a tool stops being trustworthy matters more than the cases where it works.
Which values should I know?
Required missing is The rich result is usually dropped entirely. @context is Must be schema.org or the block is ignored. Curly quotes is A CMS favourite, and fatal to JSON. These are printed on the page itself, so you do not have to take them on trust.
Does the JSON-LD Validator work on a phone?
Yes. The page is responsive and the utility works in Chrome, Safari, Firefox, Edge and Samsung Internet on both Android and iOS. There is no app to install and nothing to sign into.
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