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Preview of Schema Markup Validator

Schema Markup Validator by georgeneveu

Validate Schema.org JSON-LD structured data offline or generate it for any page using GPT-4o or Claude. Deep scan any page, fix errors, boost rich results for your microdata.

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Schema markup validatorSchema markup generator
About this extension
A browser extension for Firefox that validates existing JSON-LD on any page and generates new Schema.org markup - ready to paste in the code of your page for rich search results.

🔍 Deep Scan
Detects all existing JSON-LD blocks on the active page and validates them against Schema.org rules — spotting missing fields, wrong date formats, invalid enum values, and more.

🤖 AI Generation
Scrapes the page (title, headings, price signals, OG meta, existing schemas) and sends context to your chosen AI model, which picks the right schema type and fills every field accurately.

🔀 OpenAI & Claude
Use your own OpenAI (GPT-4o, GPT-4 Turbo, GPT-3.5) or Anthropic (Claude Sonnet, Opus, Haiku) key. Switch provider and model any time.

✅ External Validators
One-click launch of Google's Rich Results Test and Schema.org Validator for final verification before deploying to your site.

🔒 Your API keys never leave your browser
Keys are stored exclusively in the browser's sandboxed local storage — they never touch any third-party server. The only outbound requests go directly to api.openai.com or api.anthropic.com when you click Generate.
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Permissions and data

Required permissions:

  • Access your data for api.openai.com
  • Access your data for api.anthropic.com

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Version
1.0
Size
516.15 KB
Last updated
5 days ago (May 3, 2026)
Related Categories
  • Web Development
  • Search Tools
License
All Rights Reserved
Version History
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