GTmetrix is described as 'free online tool that analyzes your page's speed performance'. There are more than 25 alternatives to GTmetrix, not only websites but also apps for a variety of platforms, including SaaS, Firefox, Mac and Windows. The best alternative is Screpy. It's not free, so if you're looking for a free alternative, you could try Google Lighthouse or PageSpeed Insights. Other great sites and apps similar to GTmetrix are WebPagetest (Free, Open Source), ahrefs (Paid), DareBoost (Freemium) and Yellow Lab Tools (Free, Open Source).
- YSlow analyzes web pages and why they're slow based on Yahoo!'s rules for high performance web sites. View 21 alternatives to Yahoo! YSlow
The GitHub repository hasn't been updated since mid-2014.No screenshots yet
- Free • Open Source
- Google Chrome