SEOInspector — Real-time SEO Audit

Chrome extension (Manifest V3) for instant SEO auditing of any webpage.
47 built-in checkers · Core Web Vitals · Schema validation · Broken links · SERP preview

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Features

Category	Checkers
On-page SEO	Title, meta description, canonical, robots, hreflang, pagination
Structure	Headings hierarchy, internal/external links, link equity, TOC
Rich results	Open Graph, Twitter Cards, JSON-LD schema, schema suggestions
Performance	Core Web Vitals (LCP, CLS, FCP, INP), resource hints, fonts, CSS
Content	Word count, keyword density, readability, NLP, E-E-A-T signals
Accessibility	ARIA roles, form labels, color contrast, skip links
Security	Mixed content, exposed emails, leaked API keys, security headers
Technical	JS SEO, PWA, tech stack, third-party scripts, URL params
Tools	HTTP headers, storage inspector, robots.txt viewer, sitemap explorer, redirect chain
Extras	Broken link checker (up to 150 URLs), audit history (last 50 audits), export to HTML/CSV/Markdown

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Installation

Option A — Chrome Web Store

Install directly from the Chrome Web Store (link will be added after publication).

Option B — Developer mode (unpacked)

Use this method to run the latest source code locally.

Requirements: Google Chrome 88+

1. Clone or download this repository:

   git clone https://github.com/<your-username>/SEOInspector.git

2. Open Chrome and navigate to chrome://extensions

3. Enable Developer mode (toggle in the top-right corner)

4. Click "Load unpacked" and select the project folder (SEOInspector/)

5. The SEOInspector icon will appear in the Chrome toolbar

After any code change, click the reload button on the extension card at chrome://extensions.

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Usage

1. Navigate to any webpage you want to audit
2. Click the SEOInspector icon in the toolbar
3. Click "Аналіз" (Analyze) — results appear within seconds
4. Switch between checker tabs in the sidebar
5. Click any issue to highlight the element on the page
6. Use the Export button for HTML/PDF/CSV/Markdown report

Sidebar modes

• Local — 47 built-in checkers running entirely in your browser
• DFS — DataForSEO-powered panels (backlinks, keywords, SERP, domain stats, tech, AI)

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Options & Configuration

Open Settings via the gear icon or right-click the extension → "Options":

• Enable/disable individual checkers
• Adjust thresholds: title length, LCP/CLS/FCP limits, word count, max links, etc.
• Set DataForSEO API credentials for advanced panels
• Configure broken-link checker concurrency and timeout

Settings are stored in chrome.storage.sync and sync across your Chrome profile.

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Project Structure

SEOInspector/
├── manifest.json          # Extension manifest (MV3)
├── background.js          # Service worker: API proxies, link checker
├── content.js             # Orchestrator injected into pages
├── checkers/              # 47 checker modules (one file per checker)
├── popup.html             # Extension popup
├── popup/
│   ├── app.js             # Entry point, event wiring
│   ├── analyze.js         # Run audit, loading state
│   ├── state.js           # Global popup state
│   ├── lib/
│   │   ├── constants.js   # CHECKER_TABS, SPECIAL_PANELS, etc.
│   │   └── utils.js       # Pure helper functions
│   ├── ui/
│   │   ├── render.js      # Score, results, badges rendering
│   │   └── panel-switch.js
│   └── panels/            # Special panels (broken links, storage, headers, …)
├── api/
│   ├── cache.js           # TTL cache backed by chrome.storage.local
│   └── dataforseo.js      # DataForSEO API wrapper
├── options.html / options.js / options.css
├── i18n.js                # Ukrainian UI strings
└── icons/

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Minimum Requirements

• Google Chrome 88+
• No internet connection required for local checkers