# Schema Markup Validator

> 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.

Canonical page: [https://chrome-stats.com/d/schema-markup-validator](https://chrome-stats.com/d/schema-markup-validator)

## Overview

- **ID:** `schema-markup-validator`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** georgeneveu
- **Category:** web-development,search-tools
- **Daily users:** 26
- **Weekly downloads:** 3
- **Version:** 1.0
- **Last updated:** 2026-05-06
- **First published:** 2026-05-03
- **Size:** 516 KB
- **Data as of:** 2026-09-16
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/schema-markup-validator/)

## Description

A browser extension for Firefox that validates existing JSON-LD on any page and generates new <a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/9d9f25684d519afe48ff10aa160c7c6a1518646069374f4f4458fe60a3717c84/http%3A//Schema.org" rel="nofollow">Schema.org</a> markup - ready to paste in the code of your page for rich search results.

<strong>🔍 Deep Scan</strong>
Detects all existing JSON-LD blocks on the active page and validates them against <a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/9d9f25684d519afe48ff10aa160c7c6a1518646069374f4f4458fe60a3717c84/http%3A//Schema.org" rel="nofollow">Schema.org</a> rules — spotting missing fields, wrong date formats, invalid enum values, and more.

<strong>🤖 AI Generation</strong>
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.

<strong>🔀 OpenAI &amp; Claude</strong>
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.

<strong>✅ External Validators</strong>
One-click launch of Google's Rich Results Test and <a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/277e76a862dfc38496f477deac45d33e2890bc3eddcb56216d6af8389b7e788b/https%3A//validator.schema.org" rel="nofollow">Schema.org Validator</a> for final verification before deploying to your site.

<strong>🔒 Your API keys never leave your browser</strong>
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 <code><a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/12e27e533e8926661fcf6b0ae844bf20f199e811558bba18b332645449708001/http%3A//api.openai.com" rel="nofollow">api.openai.com</a></code> or <code><a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/708c455a1fc651daac447ff032349644a13b0ac59933b6d9ae43961b23a30062/http%3A//api.anthropic.com" rel="nofollow">api.anthropic.com</a></code> when you click Generate.

## Rankings

- #21,976 — Overall
- #4 — gpt-4o
- #217 — scraping
- #220 — x data

## Permissions and access

### Permissions

- `storage`
- `activeTab`
- `https://api.openai.com/*`
- `https://api.anthropic.com/*`

## Safety

- **Risk impact:** Moderate risk impact
- **Risk likelihood:** High risk likelihood

### Analysis details

- Request access to the following domains: openai.com, anthropic.com
- This extension has low user count. Unpopular extensions may not be stable or safe.

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

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Source: [Chrome-Stats](https://chrome-stats.com/d/schema-markup-validator)