Free SEO Chrome Extensions

Full Site Cache Auditor

Audit caching, CDN and DNS in one scan, free, right in your browser.

A free Chrome extension that runs 54 real checks on your site's caching, CDN, and DNS setup, and reports each one on its own.

Download free (zip)How to install

Version 1.0.1 for Chrome, Edge and Brave. No account needed.

Full Site Cache Auditor showing the results of a scan
Full Site Cache Auditor after a scan of an example site.

Why this matters

Caching problems are hard to spot by hand. A missing Cache-Control header, a CDN that is not actually caching your pages, or a DNS setup that adds delay, these things quietly slow your site down and can hurt both user experience and rankings. This tool checks all of it at once and tells you exactly where the issues are.

What it checks

The 54 checks cover several areas:

  • HTTP cache headers and directives, like Cache-Control, Expires, and ETag
  • CDN and edge cache detection, including which provider you are using
  • Provider specific headers for Fastly, Akamai, Cloudflare, Vercel, and Netlify
  • DNS caching and TTL behavior
  • Static asset caching for images, fonts, and scripts
  • HTML and dynamic page cache safety
  • Browser side caching, including service workers and PWA setup
  • Cache security risks, like cache poisoning
  • Cache performance and timing
  • Platform specific detection for WordPress, Varnish, Nginx, and Apache
  • Resource hints like preload and preconnect
  • AMP and signed exchange support

How it works

The tool fetches your homepage, robots.txt, sitemap.xml, and up to 15 internal pages once, then runs every check against that same data instead of fetching things over and over. A full report opens in its own tab with everything organized by category. You can export the results as an Excel file or a styled PDF report.

How to install Full Site Cache Auditor

It takes about a minute. You only do this once.

  1. Download the zip file with the button on this page and unzip it. You will get a folder called full-site-cache-auditor.
  2. Open the extensions page. In Chrome, type chrome://extensions in the address bar and press Enter. In Edge use edge://extensions, in Brave brave://extensions.
  3. Turn on Developer mode with the switch in the top right corner.
  4. Click Load unpacked and choose the unzipped folder (the one that contains manifest.json).
  5. Pin the icon from the puzzle piece menu in your toolbar, so it is always one click away.

Download Full Site Cache Auditor

Good to know

This tool works in English only. A few things are left out on purpose because there is no reliable way to check them from a browser extension, like Early Hints detection and Cloudflare Page Rules, since neither exposes anything a script can actually read.

What the permissions are for

Chrome shows these when you install. Here is what each one is used for.

storageSave your settings and scan results in your browser.
unlimitedStorageStore results for large sites with thousands of pages.
downloadsSave Excel and PDF reports to your computer.
tabsRead the address of the tab you have open, so it knows which site to scan.
Access to websitesLoad the pages of the site you scan, the same way a crawler does.

Questions

Is Full Site Cache Auditor free?

Yes. It is free to download and use, and the code is open source under the MIT license. You do not need an account, a subscription or an activation code.

Where are my results stored?

Your scan results and settings are saved in your own browser. The extension does not ask you to sign in, and you can delete everything by removing the extension.

Which browsers does it work in?

Google Chrome, and other browsers built on Chromium such as Microsoft Edge and Brave.

Do I need access to my server or CDN account?

No. It reads the public responses your site sends, the same way a visitor's browser or a crawler would.

How do I update it?

Download the latest zip from this page, replace the old folder with the new one, and click the reload button on the extensions page.

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