Page Speed Analyzer

Step-by-step guide

1. 1
   Enter a URL
   Paste the full URL you want to analyze (e.g. https://example.com). The tool will fetch the page directly from your browser.
2. 2
   Wait for the fetch to complete
   The tool measures the time from request to full HTML response, then parses the page to extract resource counts and meta tags.
3. 3
   Read your performance score
   A score from 0–100 is calculated based on best-practice checks: viewport tag, script optimisation, page size, compression, and caching.
4. 4
   Review the quick wins checklist
   Each item shows whether the page passes or fails a specific optimisation check with a plain-English explanation of the impact.
5. 5
   Handle CORS restrictions
   If the site blocks cross-origin requests, a helpful message explains why and how to measure performance using your browser's built-in DevTools Network tab instead.

Frequently Asked Questions

What does this tool measure?

It measures HTML load time (from browser fetch request to full response), page size in KB, number of script and stylesheet tags, whether scripts use async/defer, image lazy loading usage, viewport meta tag presence, compression, and cache headers.

Why does some results show CORS Restricted?

CORS (Cross-Origin Resource Sharing) is a browser security policy. When a website's server doesn't include the appropriate headers allowing external JavaScript to read its response, the browser blocks the fetch. This is not an error in the tool: it's the target site's security policy. Most CDN-served assets and APIs are CORS-permissive; full web pages often are not.

What is a good performance score?

Scores of 80–100 indicate good performance best practices. Scores of 50–79 suggest some improvements are possible. Below 50 indicates significant issues worth addressing for user experience and Core Web Vitals.

How is the score calculated?

The score starts at 100 and deducts points for common issues: missing viewport tag (-15), render-blocking scripts without async/defer (-5 each), too many total scripts (-5 per script over 5), large page size (-5 per 100KB over 500KB), missing compression (-10), and missing cache headers (-5).

Is this the same as Google PageSpeed Insights?

No. Google PageSpeed Insights uses Lighthouse to run a full lab test from Google's servers with CPU throttling and detailed metrics. This tool performs a lightweight browser-side fetch, useful for a quick sanity check but not a replacement for full Lighthouse testing.

Can I test localhost URLs?

Yes: since the fetch runs in your browser, you can test any URL accessible from your machine, including localhost and internal network addresses.

Why is the load time different each time?

Load time varies with your network conditions, server load, CDN cache state, and DNS resolution time. Run multiple checks and average the results for a more reliable baseline.

Is this tool free?

Yes, completely free with no account, no sign-up, and no API keys required.