22 Free SEO Chrome Extensions that Actually Work, Tested by the Experts

We tested the most recommended SEO extensions. This list shows you the 22 best free ones.

Learn how to use these tools to boost your SEO without spending money.

List of Tools in Full:

• SEOTesting
• Grammarly
• Keyword Surfer
• Racoon SEO Link Checker
• Glimpse
• SimilarWeb
• Similar Sites
• Schema Builder
• View Rendered Source
• Link Redirect Trace
• SEO Search Simulator by NightWatch
• Detailed
• SEO Minion
• MozBar
• Link Grabber
• Hunter
• Siteimprove Accessibility Checker
• SEOQuake
• NoFollow
• Redirect Path
• META SEO Inspector
• Tag Assistant

SEOTesting

The SEOTesting Chrome extension helps with daily tasks and on-page SEO.

Top features:

• Find the page’s top queries
• See easy-to-read graphs with clicks, impressions, average position, and CTR
• View current SEO tests
• Get quick access to SEOTesting reports

This gives you Google Search Console data while browsing. You don’t need to open the SEOTesting dashboard every time. That saves big time.

Free features available to everyone:

• Canonical URL detection
• Meta robots tag detection
• Page word count
• Link count (separates internal and external links)
• Image count and missing alt text check
• Document heading structure

The document structure feature helps confirm content and headings are correct.

Pro tip: Click on any heading to scroll to that element. Hover your mouse to highlight it.

Grammarly

Grammarly offers a free browser extension. It gives grammar, spelling, and tone suggestions. This keeps your writing sharp everywhere.

This extension helps you avoid awkward mistakes.

Grammarly’s free plan is generous. You can set a preferred tone. This helps you write consistently.

Why it matters for SEO: Good writing improves user experience. Better content often ranks higher.

These tailored suggestions make Grammarly easy to use.

Keyword Surfer

Keyword Surfer shows search volume and CPC for keywords in the SERP.

They have search volume data for over 70 countries. This includes the USA, UK, Australia, France, and Germany.

SERP features:

• Shows estimated website traffic
• Displays words on the page
• Counts exact matches for the query
• Alerts you when Google rewrites page titles

The title rewrite feature is a game-changer. Google often changes title tags now.

The sidebar widget shows:

• Keyword ideas
• Similarity to current query
• Search volume for each keyword

Press the star to save keyword ideas to your clipboard.

Racoon SEO Link Checker

Racoon SEO Link Checker is a free extension. It helps you track and manage links in one browser window.

Find every link on a page. Check the health of each one. See if it’s indexed and has correct attributes.

Key features:

• Identify link attributes (dofollow, nofollow, sponsored)
• Detect noindex meta tags
• Check indexing status via X-Robots-Tag headers
• Confirm indexing in Google search results
• Scroll to detected links instantly
• Copy link details to clipboard
• Set domains to check or exclude
• Export reports to Google Sheets

This saves time on manual link checking. It makes link management more efficient.

Glimpse

Glimpse enriches your Google Trends experience.

Features include:

• Search volume data
• Interest trajectory (removes seasonality)
• Email alerts for tracking keywords
• Shows which channel mentions keywords most
• People Also Search For keywords
• Topic Map visualization

Glimpse helps spot new trends before they go mainstream. This helps you become an authority on new topics. SEO competition stays low early on.

Subscribe to their newsletter. Get 2 exponential trends per month in your inbox.

Free plan: 10 searches per month. Just create an account to start.

SimilarWeb

SimilarWeb shows key website metrics instantly.

Metrics displayed:

• Monthly visitors
• Bounce rate
• Average visitor duration
• Global ranking
• Top visiting countries
• Traffic sources (search, direct, social, email, ads, referrals)

The extension is 100% free. You just need to join their contributor network. This means you share information about sites you visit with SimilarWeb.

Great for competitor research. Pair it with SimilarSites for deeper insights.

Similar Sites

Similar Sites shows related websites to the one you’re viewing.

Main use case: Finding your main competitors. This helps when you don’t know much about a niche. You don’t have to rely on guesswork.

This extension helps SEO agencies research competitor sites for new clients.

Click the extension icon when visiting any site. It shows a panel with data.

The panel also shows estimated monthly visitors for competitors. See their ranking in the category too.

You need to sign up for the SimilarWeb contributor program.

Schema Builder

Schema.dev created this extension. It helps you see a page’s markup.

The extension helps you write Schema. It also validates existing Schema on pages. Fix any errors with little effort.

Easy to use and test markup with one button click.

Schema Builder works great for adding structured data to ecommerce stores.

The extension shows markup requirements and recommendations when you test and deploy.

View Rendered Source

This extension shows how browsers render pages versus original source code.

SEOs use this to see what the DOM looks like. This shows what search engines see.

Catch errors before Google does. Otherwise, Google might index the improperly rendered version.

This prevents errors caused by JavaScript during rendering. Examples include missing titles and meta descriptions.

Three code sections:

• Raw: HTML source code from browser’s ‘View Source’
• Rendered: Page as rendered in current browser (includes JavaScript changes)
• Difference: Changes JavaScript made between raw and rendered source

Link Redirect Trace

Link Redirect Trace (LRT) helps diagnose and analyze redirect errors.

This extension differs from alternatives. It shows errors, how to fix them, and their impact on your site.

Features:

• Detects redirect loops for current pages
• Shows HTTP codes for each redirect
• Alerts if robots.txt blocks crawling
• Detects canonical tags
• Shows meta robots tags
• Displays raw HTTP header data

Everything is free. No account creation needed.

SEO Search Simulator by NightWatch

SEO Search Simulator simulates Google searches from different locations in real time.

You don’t need VPNs to see how pages rank in different countries. It removes personalized Google results too.

Great alternative to logging into rank tracker tools for quick checks.

Also helpful for checking competitor rankings for specific queries.

The search simulator saves searches. Handy when you use the same query repeatedly.

Detailed

The Detailed SEO Extension helps with on-page SEO checks.

Overview section shows:

• Page title
• Meta description
• Canonical URL
• Robots tag and X-Robots tag
• Meta keywords
• Word count
• Page language from HTML

Detailed has shortcuts for robots.txt and XML sitemaps. But they guess where these files are located. If files don’t exist, shortcuts lead to 404 pages.

Other features:

• Page heading hierarchy
• Export page links
• Download page images
• View structured data (schema markup)
• Open Graph for social media

SEO Minion

SEO Minion has many capabilities. The SERP preview function shows how title and meta description changes look in search results.

This prevents you from following SEO tool character recommendations that cut off titles and descriptions.

Everyday tasks:

• Find broken links
• Check page HTTP status codes
• Find internal links
• Verify if pages are indexable

On-page elements it finds:

• Word count
• Title and meta description (warns if too long)
• Canonical URL and meta robots tags
• Page headings
• Image count and missing ALT text
• Open Graph metadata

SERP widget shows:

• Total results on page
• Ads versus organic results
• Rich results like product listings or FAQ data

Bonus feature: Download People Also Ask (PAA) questions and answers as CSV files for research.

MozBar

MozBar analyzes pages for free. It checks load time, canonicals, status codes, and markup.

In SERPs, this extension shows Moz’s popular metrics: Domain Authority (DA) and Page Authority (PA).

Free plan includes link metrics from 3 places:

• Page analysis by clicking the extension icon
• Exporting search results to CSV files
• Clicking “Link Analysis” text in SERP info boxes

Common use case: Link-building campaigns. See which top SERP results have the highest authority.

Link Grabber

Link Grabber collects all links from HTML pages with one button click. It displays them in a list.

A great tool when Screaming Frog is unavailable. Perfect for quick checks. Copy links into spreadsheets for analysis.

Features:

• Group links by domain
• Hide duplicates
• Block domains to remove them from lists

Hunter

Hunter’s browser extension finds email addresses on the web easily.

The free plan includes 25 searches per month. Enough for occasional use.

When Hunter finds email addresses on sites you visit, it lights up (turns orange). Stays gray when it doesn’t find any. The extension works in the background.

Click the extension icon. See a pop-up with known email addresses and URL sources where they were found.

Siteimprove Accessibility Checker

The Siteimprove Accessibility Checker finds insights about website accessibility.

This tool lists all accessibility issues. Shows how often they happen on pages. It points to elements responsible for warnings.

The accessibility checker helps when advising potential clients. Show examples of how they can improve accessibility compliance.

Straightforward extension for improving web experiences for users with disabilities.

SEOQuake

SEOQuake handles a wide range of SEO tasks for free.

Quick page diagnosis shows:

• Link numbers (internal, external, nofollow)
• Canonical tags
• Images without ALT text
• Robots.txt and XML sitemap detection
• Most used words or phrases and their density

Google SERP features:

• Info box below each result
• Shows indexed pages for domains
• Displays backlink numbers
• Export button on SERP left side

Also includes an ‘SEO bar’ for browsing with domain metrics.

NoFollow

NoFollow highlights nofollow links on web pages with visual indicators.

This extension makes link analysis much faster. Instead of checking HTML code, you see nofollow links instantly.

Key features:

• Highlights nofollow links with red dotted borders
• Shows sponsored and UGC link attributes
• Works on any webpage automatically
• No setup required

Why it’s useful:

• Quick link audits for your site
• Competitor link analysis
• Verify your own link implementations
• Check if external links pass authority

Perfect for link builders who need to assess link value quickly. Also helps with internal link audits.

Redirect Path

Redirect Path shows the complete redirect chain for any URL you visit.

When pages redirect multiple times, this extension maps the entire journey. You see every step and status code.

Features include:

• Visual redirect chain display
• HTTP status codes for each redirect
• Final destination URL
• Redirect type identification (301, 302, etc.)
• Error detection in redirect loops

Common use cases:

• Fix broken redirect chains
• Identify unnecessary redirects that slow page speed
• Verify 301 redirects work correctly
• Audit competitor redirect strategies

Essential for technical SEO audits. Helps prevent PageRank loss from poor redirects.

META SEO Inspector

META SEO Inspector displays meta tags, headings, and images in an organized format.

This extension gives you a quick on-page SEO overview without viewing source code.

What it shows:

• All meta tags (title, description, keywords)
• Heading structure (H1, H2, H3, etc.)
• Image information and alt text
• Canonical URLs
• Open Graph tags
• Twitter Card data

Visual indicators:

• Missing meta descriptions show in red
• Duplicate content warnings
• Proper heading hierarchy checks
• Image optimization alerts

Perfect for:

• Quick page audits
• Content optimization checks
• Social media tag verification
• Multi-page analysis

Saves time compared to manual source code inspection. Great for content creators and SEO beginners.

Tag Assistant

Tag Assistant helps you install and troubleshoot Google tags on your website.

This official Google extension works with gtag.js and Google Tag Manager. It shows which Google tags are present on any page you visit.

Core features:

• Displays Google tags found on pages in a side panel
• Works with Google Analytics, Google Ads, and Tag Manager
• Shows tag presence instantly when you navigate to pages
• Connects to tagassistant.google.com for advanced debugging

Troubleshoot mode:

• Advanced debugging tool for detailed diagnostics
• Works within iframes and across entire sessions
• Helps validate, diagnose, and resolve implementation issues
• Session data available for review on Google’s platform

Perfect for:

• Verifying Google Analytics installation
• Checking Google Ads conversion tracking
• Debugging Tag Manager implementations
• Ensuring tags fire correctly across your site

Essential for any site using Google’s marketing and analytics tools. Helps ensure your SEO efforts get properly measured and tracked.

My Essential SEO Extension Setup

After years of testing, these five extensions form the core of my daily SEO workflow:

1. SEOTesting
2. Grammarly
3. Keyword Surfer
4. SimilarWeb
5. Schema Builder

Start with these five. Add others based on your specific needs.

Final Thoughts

These 22 free extensions have transformed how I approach SEO work. They’ve helped me:

• Cut my analysis time by some distance
• Catch technical issues before they impact rankings
• Research competitors more effectively
• Validate structured data without coding knowledge

The best part? Every tool costs nothing. You can build a professional SEO toolkit without spending a penny.

Remember: Extensions are just tools. They work best when you understand SEO fundamentals. Use them to enhance your knowledge, not replace it.

I regularly update this list as new extensions emerge and existing ones evolve. The SEO landscape changes fast. Your toolkit should adapt with it.

Ready to take your SEO analysis to the next level?

While these free extensions provide excellent value, sometimes you need deeper insights.

SEOTesting goes further than any extension ever could:

• Google Search Console data longer than the sixteen-month limit.
• Easy to set up and run SEO tests, including time-based and split tests.
• A wide range of reports so you can make better use of your GSC data.

Get started with SEOTesting’s free features today! We have a 14-day free trial for you to make use of, so you can decide whether the tool is worth it for you and your team. Once you’ve finished the trial, we start at just $50 per month!

Try SEOTesting Free →

Note: While SEOTesting is a paid tool, our Chrome extension provides valuable free functionality that every SEO professional can benefit from.