🔍 Free SEO Extension | Schema Validator | Core Web Vitals Checker

Best SEO Extension for Chrome: 40+ Instant SEO Checks While You Browse

InsightCrawl runs 40+ on-page, technical, schema, and AI readiness checks the moment a page loads, letting you replace Schema.org validators, PageSpeed dashboards, and hreflang spreadsheets with one privacy-first extension.

40+
Instant Checks
100%
Local Processing
Free
Schema Validations
Install Extension See How It Works

Works on all Chromium browsers:

Chrome Edge + Brave, Opera, Vivaldi, Arc, Comet & more

Install once, use everywhere you browse

✓ Stop bouncing between Schema validators, PageSpeed Insights, hreflang spreadsheets, and llms.txt scripts - InsightCrawl handles every audit as you browse

🔒 All processing happens locally, your data never leaves your device

InsightCrawl SEO Extension - On-Page SEO Analysis showing title tags, meta descriptions, and heading structure

Choose the Features You Need

Every major SEO task, on page polish, technical diagnostics, schema QA, and AI readiness lives inside InsightCrawl. Choose a path to see what is included.

What it analyzes:

  • Title Tags: Character count, pixel width warnings, duplicate detection across pages
  • Meta Descriptions: Length validation, CTR optimization suggestions, missing meta alerts
  • SERP Preview Lab: Live desktop/mobile snippet rendering, truncation visualization, emoji support testing
  • Heading Structure: H1-H6 hierarchy map, duplicate H1 detection, semantic outline validation
  • Link Intelligence: Internal vs external ratio analysis, broken link detection, anchor text optimization
  • Canonical URLs: Self-referencing validation, cross-domain canonical warnings
  • Hreflang Tags: Locale coverage, bidirectional linking, return tag verification

Who needs this:

Content Teams

Optimize SERP snippets before publishing, ensure all metas within limits, fix heading hierarchy issues

Agencies

Audit client pages in 10 minutes, scan meta tags, and highlight quick wins for client presentations.

SEO Consultants

Identify low-hanging fruit (missing metas, duplicate H1s, broken canonicals) instantly

Pro Tip:

Use the live pixel counter to see exactly how your title displays in Google search results—no more guessing if it gets truncated. Mobile preview shows exact mobile SERP rendering.

Install Extension
InsightCrawl On-Page SEO Analysis - Title tag analyzer, meta description checker, and heading structure validation

Real-time character counts, pixel widths, and live SERP preview

25+ On-page checks
Instant Results

What it measures:

  • Largest Contentful Paint (LCP): Main content render time, element identification, optimization paths.
  • Cumulative Layout Shift (CLS): Layout stability scoring, shifting elements highlighted, fix recommendations.
  • First Input Delay (FID) / INP: Interaction responsiveness measurement, JavaScript blocking detection.
  • First Contentful Paint (FCP): Initial render timing analysis.
  • DOM Complexity: Total element count, nesting depth analysis, performance impact warnings
  • Script Inventory: Render-blocking scripts identified, async/defer recommendations, third-party script audit
  • Image Optimization: Lazy loading detection, oversized image warnings, modern format suggestions (WebP, AVIF)
  • Mobile Viewport: Configuration validation, responsive design verification
  • Security Headers: HTTPS enforcement check, Content Security Policy validation

Who needs this:

Developers

Debug performance regressions instantly, no PageSpeed API delays, test on staging/localhost environments

Agencies

Pre-launch QA for client sites, catch Core Web Vitals issues before deploy, deliver performance reports

In-House Teams

Monitor every release for regressions, track LCP/CLS/FID trends, ensure no SEO performance drops

vs PageSpeed Insights:
  • Instant results in one place
  • Works on staging environments and localhost
  • No API rate limits or quota restrictions
  • Test while browsing naturally—no URL submissions
  • Multiple profile support across browsers
Install Extension
InsightCrawl Technical SEO Audit - Core Web Vitals checker showing LCP, CLS, and FID metrics

Live Core Web Vitals scoring with actionable recommendations

LCP 2.1s Good
CLS 0.05 Good
FID 120ms Needs Work

What it validates:

  • JSON-LD Schemas: Syntax validation, type compatibility (Product, Article, LocalBusiness, Recipe, Event), required properties verification
  • Microdata Markup: itemscope/itemtype/itemprop validation, nesting hierarchy checks, property value verification
  • RDFa Implementation: vocab/typeof/property attribute validation, namespace checking
  • Rich Result Eligibility: Google rich snippet requirements (star ratings, price, availability for Product schema)
  • Error Detection: Missing required fields, invalid property values, type mismatches, nesting errors
  • Complex Structures: Nested schema relationships (Product with Offers, Article with Author and Publisher)
  • Multiple Schemas: Detect all schema types on single page, validate each independently
  • Testing: Copy validated JSON-LD, one-click deep link to Google Rich Results Test

Supported schema types:

Product Article LocalBusiness Recipe Event Organization Person FAQ HowTo Review VideoObject BreadcrumbList

Who needs this:

E-commerce Sites

Validate Product schema across thousands of SKUs, ensure star ratings display in search, catch missing price/availability

Publishers

Verify Article and NewsArticle markup, check AMP compatibility, validate Author and Organization schemas

Local Businesses

Validate LocalBusiness schema for Google Maps and Knowledge Panel, verify opening hours and address data

Developers

Debug schema implementation without external validators, test locally before deployment, copy validated JSON-LD

FREE TIER UNLIMITED:

Unlike Schema.org validators that charge $20-50/month, InsightCrawl gives you unlimited schema validation in the free tier forever. No page limits, no monthly caps, validate as many pages as you need.

Install Extension
InsightCrawl Schema Validator - JSON-LD validator showing structured data validation and error detection

Instant JSON-LD validation with detailed error reporting

ERROR Missing required property: "price"
WARNING Recommended: "aggregateRating"
VALID Product schema eligible for rich results

One-click deep link to Google Rich Results Test for additional validation

What it detects:

  • Hreflang Networks: Return tag verification, locale coverage analysis, bidirectional linking validation
  • llms.txt Detection: llms.txt and llms-full.txt file detection, content feed identification
  • Content Feeds: RSS, Atom, JSON Feed detection and validation
  • Entity Clarity: Content structure analysis for AI search engines, semantic markup detection
  • AI Readiness Scoring: Overall readiness assessment for AI-powered search and assistants

Who needs this:

International Sites

Verify hreflang implementation across all locales, ensure proper return tags, validate language targeting

Content Publishers

Ensure llms.txt files are properly configured for AI crawlers, validate content feeds for AI indexing

Future-Proof Sites

Prepare for AI-powered search engines, optimize content structure for AI assistants and chatbots

Install Extension
InsightCrawl AI Readiness Analysis - Hreflang validation and llms.txt detection for AI search engines

AI readiness scoring and hreflang network validation

Install InsightCrawl

Works wherever you browse: install from Chrome Web Store or Edge Add-ons and InsightCrawl instantly unlocks in Chrome, Edge, Brave, Opera, Vivaldi, Arc, Comet, and every Chromium-based browser. One install powers every profile.

Universal Chromium Compatibility

Install InsightCrawl once and launch it instantly in Chrome, Edge, Brave, Opera, Vivaldi, Arc, Comet, and any Chromium browser - perfect for QA across multiple browser profiles.

Chrome Web Store

Install InsightCrawl for Google Chrome

Install on Chrome

Microsoft Edge Add-ons

Install InsightCrawl for Microsoft Edge

Install on Edge

How InsightCrawl Works

Get instant SEO reports with schema validator, Core Web Vitals checker, and meta tag analyzer in 4 simple steps

1

Install InsightCrawl in Any Chromium Browser

Install InsightCrawl from Chrome Web Store or Edge Add-ons, then use it in Chrome, Edge, Brave, Opera, Vivaldi, Arc, Comet, or any Chromium browser. Pin it to your toolbar for instant access to unlimited schema validation plus 40+ advanced SEO checks.

2

Visit Any Webpage

Navigate to any webpage you want to analyze. Click the extension icon and get instant SEO analysis: schema validation, Core Web Vitals scores, meta tag checks, and technical audit results.

3

Review SEO Issues Instantly

See all detected issues: missing alt tags, schema errors, Core Web Vitals problems, meta tag issues, and heading structure problems. Fix them with clear, actionable recommendations.

4

Upgrade to Pro for Advanced Features

Unlock advanced on-page SEO audits (25+ checks), comprehensive technical diagnostics, AI-powered optimization tips, and unlimited analysis. Start free, upgrade anytime.

🔍

Schema Validator & JSON-LD Checker

One click reveals all Schema.org markup. Test structured data instantly with our JSON-LD validator, Microdata checker, and RDFa analyzer.

⚠️

Real-Time Error Detection

Highlights missing alt tags, schema errors, meta tag issues, and Core Web Vitals problems in real time to prevent costly SEO mistakes.

🔒

Strict Privacy

All processing happens locally. Pages are scanned and results delivered in your browser, no data ever leaves your device.

Schema Analysis
Error Detection
Privacy-First

InsightCrawl in Action

See how InsightCrawl helps you debug and identify schema issues so you know exactly what needs to be improved

Before InsightCrawl

SEO Score: 62/100

Issues Detected:

  • ❌ Missing meta descriptions on 15 pages
  • ❌ No structured data/schema markup
  • ❌ Poor Core Web Vitals (LCP: 4.2s)
  • ❌ Duplicate H1 tags detected
  • ❌ Images missing alt attributes

After Using InsightCrawl

Issues Identified & Fixed

Issues Identified and Fixed:

  • ✅ Added optimized meta descriptions
  • ✅ Implemented JSON-LD schema markup
  • ✅ Optimized images, improved LCP to 2.1s
  • ✅ Fixed heading structure hierarchy
  • ✅ Added descriptive alt text to all images
Result: +47% improvement in organic traffic within 30 days

"InsightCrawl identified 15 critical issues we completely missed with other tools, including 12 missing meta descriptions, duplicate H1 tags, and schema markup errors. The clear debugging information made fixing everything straightforward, even for our junior team members. We replaced 3 separate paid tools with InsightCrawl."

Digital Agency Client E-commerce Website Audit • Found 15 issues in 5 minutes

What's Free vs Pro?

Start with our free version: unlimited schema validation plus 40+ instant SEO checks. Upgrade to Pro ($9.9/mo) for advanced on-page intelligence, Core Web Vitals diagnostics, AI readiness workflows, and llms.txt/hreflang automation.

Features
Free
$0
Pro
$9.9/mo
Schema & Structured Data Analysis Unlimited JSON-LD, Microdata & RDFa validation plus OG/Twitter previews
Copy-Ready JSON & Google Rich Results Shortcuts Copy structured data or deep-link into Google's tester in one click
llms.txt Monitoring & Structured Data Tools Detect llms.txt/llms-full.txt status, copy validated schema, and jump into Google’s tester
Advanced On-Page SEO: Part of 40+ Checks Title optimization, heading hierarchy analysis, internal linking patterns, keyword density, content structure validation
AI Optimization & International Signals Hreflang validation, robots.txt/feeds analysis, AI-readiness scoring
Technical SEO Diagnostics: Part of 40+ Checks Core Web Vitals scoring, lazy loading detection, mobile viewport validation, JavaScript rendering analysis, DOM complexity
Install Extension

Trusted by SEO Professionals

See how agencies, solo consultants, and in-house teams use InsightCrawl to find and fix SEO issues faster

A
Agencies SEO Agencies

Audit 100+ client pages in minutes, find quick wins for presentations. Replace multiple paid tools with one extension.

Fast Audits Client Reports All-in-One
C
Consultants Solo SEO Consultants

Identify low-hanging fruit instantly: missing metas, duplicate H1s, broken canonicals. No more switching between tools.

Quick Wins Instant Results Time Saver
I
In-House Teams Marketing Teams

Monitor every release for regressions, track Core Web Vitals trends, ensure no SEO performance drops.

Monitoring Performance QA

Loved by SEO Professionals

See how InsightCrawl helps agencies, solo consultants, and in-house teams find and fix SEO issues faster

★★★★★

"During a site migration audit, InsightCrawl surfaced 12 missing canonical tags, 5 schema errors, and 18 orphaned headings in under two minutes. The AI fix order lets my agency team deliver client-ready reports without juggling five different tools."

SM
Sarah M.
SEO Consultant, Agency Owner
★★★★★

"The free tier alone caught 8 Product schema mistakes, 32 missing image alts, duplicate OG tags, and even told me my llms.txt file was missing - stuff my $50/month tool never surfaced. I fixed everything in one pass using the live validators and shipped the client update in an afternoon."

MJ
Mike J.
Web Developer, Solo Consultant
★★★★★

"Real-time analysis as I browse is a game-changer. InsightCrawl flagged six blocked JavaScript resources, hreflang gaps, a missing llms.txt file, and a Core Web Vitals issue (LCP 4.2s → 2.1s) in the same audit. Our in-house team now runs every release through it before it ships."

AL
Alex L.
Marketing Manager, In-House Team

Frequently Asked Questions

Everything you need to know about the best SEO extension for Chrome

Is InsightCrawl a free SEO extension?

Yes, InsightCrawl offers a powerful free SEO extension. The free tier focuses on unlimited schema & structured data validation (JSON-LD, Microdata, RDFa), OG/Twitter previews, and one-click Google Rich Results testing, and everything is processed locally so nothing ever leaves your browser. Upgrade to Pro when you need the full on-page, technical, and AI readiness feature set.

What makes InsightCrawl the best SEO browser extension?

InsightCrawl combines 5+ SEO tools in one extension: schema validator, Core Web Vitals checker (LCP and CLS), meta tag checker, title tag analyzer, alt text checker, heading structure checker, and technical SEO audit tool. Unlike other SEO extensions, InsightCrawl works entirely offline with 100% local processing. No uploads, no waiting, instant results as you browse.

How does the schema validator work?

One click reveals all Schema.org markup including JSON-LD, Microdata, and RDFa. Our schema markup checker validates structured data in real-time, highlights missing properties, and ensures rich result eligibility. Test structured data on any page instantly. The free version includes unlimited schema validation with no page limits.

Is this a PageSpeed Insights alternative?

Yes, InsightCrawl is the best PageSpeed Insights alternative. Our Core Web Vitals checker measures LCP (Largest Contentful Paint), CLS (Cumulative Layout Shift), and provides actionable optimization insights. Unlike PageSpeed Insights, you get instant results without uploading URLs or waiting for server processing. Works as a web vitals extension directly in your browser.

What SEO checks does the meta tag checker include?

Our meta tag checker analyzes: title tags with live character counts, meta descriptions with CTR optimization suggestions, OG tags (Open Graph validator), Twitter cards, canonical URLs, and heading structure (H1 checker and heading hierarchy). Get instant feedback on duplicate or missing tags with actionable recommendations.

Does it include an alt text checker and image SEO tool?

Yes, InsightCrawl includes comprehensive image SEO checking: alt text checker to find missing alt attributes, image SEO checker to detect broken and oversized images, image optimization tool with size recommendations, and responsive images checker for mobile optimization. All images are highlighted directly on the page for easy fixes.

What is a technical SEO audit tool?

InsightCrawl's technical SEO audit includes: crawlability checker (robots.txt and indexing analysis), Core Web Vitals scoring, mobile viewport validation, JavaScript rendering detection, DOM complexity assessment, and security checks. Get a complete website SEO checker that identifies technical issues affecting search rankings.

Is my data secure with this SEO extension?

100% secure and private. All processing happens locally in your browser. Pages are scanned and results delivered instantly without any data leaving your device. No cloud uploads, no server processing, no data collection. Your site URLs and audit information stay completely private.

What browsers does this SEO toolbar work with?

Works on all Chromium browsers: Chrome, Edge, Brave, Opera, Vivaldi, Arc, Comet, and any Chromium-based browser. Install from Chrome Web Store or Edge Add-ons, then use it anywhere you browse. One installation works across all Chromium browsers.

What's the difference between Free and Pro?

Free version includes: unlimited schema & structured data validation (JSON-LD, Microdata, RDFa), copy-ready snippets, and direct links to Google’s Rich Results Test, making it perfect for daily QA. Pro version ($9.9/month) adds: the full 40+ signal stack: on-page intelligence, Core Web Vitals & technical diagnostics, and AI/hreflang/llms scanners. Start free, upgrade anytime.

Get the Best SEO Extension for Chrome

Install InsightCrawl: free SEO extension with unlimited schema (JSON-LD, Microdata, RDFa) validation and upgradeable Core Web Vitals, on-page, and AI readiness workflows. Get instant SEO reports with 40+ checks performed entirely on-device.

Install on Chrome Install on Edge

Free schema analysis • Pro from $9.9/month • Cancel anytime