Free tools to boost your SEO strategy
Identify Slow Loading Resources
Find the exact files slowing your page down. This tool lists the slowest and heaviest resources on any webpage, plus render-blocking scripts and styles to fix first.
What is the Slow Resource Finder?
Slow pages are almost always caused by a handful of heavy or slow-loading files. Our free tool helps you identify slow loading resources on any webpage — it loads the page through Google Lighthouse, times every single request, and shows you the slowest and largest files in a clear, ranked list. You also get a breakdown of which render-blocking scripts and stylesheets are holding up your page, so you know exactly what to fix first to make your site faster.
Example: finding a 3.8 MB analytics script nobody noticed
Your homepage scores poorly on speed tests but the HTML is tiny. The Slow Resource Finder reveals a third-party analytics script weighing 3.8 MB and loading synchronously. Switching it to async and deferring it below the fold cuts the total blocking time from 1,400 ms to 320 ms.
A forgotten analytics script
Synchronous load blocked rendering
Async + deferred loading
Key Features
Slowest Resources, Ranked
See the 15 slowest files on your page ordered by load time, so you can immediately spot what is dragging your speed down.
Largest Files by Weight
Identify the heaviest resources by transfer size — oversized images, bloated scripts, and uncompressed assets that waste bandwidth.
Render-Blocking Detection
Find the scripts and stylesheets that block your page from displaying, complete with the estimated time you could save by deferring or removing them.
Weight by Resource Type
A visual breakdown of how much of your page weight comes from JavaScript, CSS, images, fonts, and other resource types.
How to Use This Tool
Enter your URL
Paste any webpage address — your own site or a competitor's — into the input field.
Choose mobile or desktop
Select the device type you want to test. Mobile often reveals slower resources because of throttled connections.
Review the slowest and largest files
Use the Slowest, Largest, and Render-Blocking tabs to see exactly which resources to optimise, compress, defer, or remove.
Fix and re-test
Compress large images, minify and defer scripts, remove unused files, then run the tool again to confirm the improvement.
Why This Matters for SEO
Every extra file your page loads adds to its total load time, and slow pages directly hurt your rankings, bounce rate, and conversions. Google uses Core Web Vitals as a ranking factor, and the biggest culprits behind poor scores are usually a small number of slow or oversized resources. By pinpointing exactly which files are slow — rather than guessing — you can make targeted fixes that deliver the biggest speed gains for the least effort, improving both your search visibility and the experience for every visitor.
Frequently Asked Questions
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