Saturday, June 11, 2016

How to Test Page Speed for Locally Hosted Websites?

You don't want to test your web page speed after the live installation of your website.

The best way to test page speed on local machine is to use YSlow Firefox extension tool.

YSlow analyzes web pages and why they're slow based on Yahoo!'s rules for high performance web sites

Yahoo!'s Exceptional Performance team has identified 34 rules that affect web page performance. YSlow's web page analysis is based on the 23 of these 34 rules that are testable. Click each performance rule below to see the details.

  1. Minimize HTTP Requests
  2. Use a Content Delivery Network
  3. Avoid empty src or href
  4. Add an Expires or a Cache-Control Header
  5. Gzip Components
  6. Put StyleSheets at the Top
  7. Put Scripts at the Bottom
  8. Avoid CSS Expressions
  9. Make JavaScript and CSS External
  10. Reduce DNS Lookups
  11. Minify JavaScript and CSS
  12. Avoid Redirects
  13. Remove Duplicate Scripts
  14. Configure ETags
  15. Make AJAX Cacheable
  16. Use GET for AJAX Requests
  17. Reduce the Number of DOM Elements
  18. No 404s
  19. Reduce Cookie Size
  20. Use Cookie-Free Domains for Components
  21. Avoid Filters
  22. Do Not Scale Images in HTML
  23. Make favicon.ico Small and Cacheable
How to Install YSlow in Firefox

YSlow for Firefox needs Firebug to run. Obtain the latest version of Firebug from Firebug documentation is available at

Once Firebug is installed, download YSlow for Firefox from Follow the prompts to install the tool.