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StructuredValidator
What StructuredValidator is
StructuredValidator is a web tool for checking structured markup, with validation focused on JSON-LD. Users can paste JSON-LD or HTML and see results as they type. It detects Microdata and RDFa in pasted HTML but validates JSON-LD only, checking syntax, contexts, types, property names, value formats, @id references, and required or recommended properties for supported rich-result features. A URL tool fetches public HTTP and HTTPS pages, extracts JSON-LD from server HTML, and validates it in the browser without rendering JavaScript. URL fetches are limited to four redirects, eight seconds, 2 MB per page, and 12 per minute per visitor. A comparison view puts two schema implementations side by side to show differences, missing properties, and coverage. It also offers a rich-result preview and API access. The tool is free and has no authentication system. Validation history and preferences are stored in browser storage; optional AI fix suggestions send markup and validation errors to an AI provider, whose retention policy applies.
Who it suits
It is intended for SEO professionals and developers checking JSON-LD or comparing schema implementations. It may suit users who want browser-based validation without an account.
What it does well
- Results appear as users type.
- Checks JSON-LD syntax and common schema properties.
- Compares two implementations side by side.
- Validation data is not retained on the service's servers.
- Free to use on the web.
What to know first
- Validates JSON-LD only.
- URL checks do not render JavaScript.
- URL fetches have size, time, redirect, and rate limits.
- Optional AI suggestions send markup and errors to an AI provider.
Limits
The Free plan costs nothing and is described as a free tool. URL checks allow four redirects, take up to eight seconds, accept pages up to 2 MB, and are limited to 12 fetches per minute per visitor; the tool validates JSON-LD only.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Free | Free tool; no signup stated | Free |
As structuredvalidator.com lists them, read 3 Oct 2026. The maker's own page has the final word.
Getting started
- Open https://structuredvalidator.com/ in a web browser.
- Paste JSON-LD or HTML to see validation results as you type.
- Enter a public HTTP or HTTPS address to check JSON-LD in its server HTML.
- Use the comparison tool to review two schema implementations side by side.
Verdict
StructuredValidator offers immediate JSON-LD checks, URL validation, and side-by-side comparison in a free web tool. Note that pasted Microdata and RDFa are detected but not validated, and URL checks use server HTML without rendering JavaScript.
Questions
How much does StructuredValidator cost?
The Free plan costs nothing. The pricing note describes it as a free plan.
Does it validate Microdata and RDFa?
It detects Microdata and RDFa in pasted HTML, but validates JSON-LD only.
Can I check a webpage by URL?
Yes. The URL tool fetches public HTTP or HTTPS server HTML and validates extracted JSON-LD in the browser without rendering JavaScript.
Does it require an account?
The privacy policy says the service has no authentication system and does not collect login credentials.
What happens when I use AI fix suggestions?
You must request them explicitly. The markup and validation errors go to an AI provider via Vercel AI Gateway, and retention follows that provider’s policy.
Facts from StructuredValidator's own pages
- AI data retention
- AI request retention follows the AI provider's data retention policy. · structuredvalidator.com, 3 Oct 2026
- Audience
- The maker describes the tool as intended for SEO professionals and developers. · structuredvalidator.com, 3 Oct 2026
- Comparison
- The comparison tool shows two schema implementations side by side to identify differences, missing properties, and coverage. · structuredvalidator.com, 3 Oct 2026
- How to use
- Users can paste JSON-LD or HTML for validation, and results appear as they type. · structuredvalidator.com, 3 Oct 2026
- No account
- The privacy policy says the service has no authentication system and does not collect login credentials. · structuredvalidator.com, 3 Oct 2026
- Optional AI
- AI fix suggestions require an explicit user action and send the schema markup and validation errors to an AI provider via Vercel AI Gateway. · structuredvalidator.com, 3 Oct 2026
- Privacy
- Validation history and preferences are stored in browser storage, and the privacy policy says validation data is not retained on the service's servers. · structuredvalidator.com, 3 Oct 2026
- Purpose
- StructuredValidator checks JSON-LD markup and explains problems with numbered proof marks, plain-English fixes, and the relevant Google or schema.org rule. · structuredvalidator.com, 3 Oct 2026
- Supported markup
- It detects Microdata and RDFa in pasted HTML but validates JSON-LD only. · structuredvalidator.com, 3 Oct 2026
- URL limits
- URL testing accepts public HTTP and HTTPS addresses and limits fetches to four redirects, eight seconds, 2 MB per page, and 12 fetches per minute per visitor. · structuredvalidator.com, 3 Oct 2026
- URL testing
- The URL tool fetches a page's server HTML, extracts JSON-LD blocks, and validates them in the browser without rendering JavaScript. · structuredvalidator.com, 3 Oct 2026
- Validation checks
- It checks JSON syntax, contexts, types, property names, value formats, @id references, and required or recommended properties for supported rich-result features. · structuredvalidator.com, 3 Oct 2026
Where StructuredValidator stands on Freedom251
- Schema Markup Tools#16 of 24