Yahoo! YSlow is described as 'YSlow analyzes web pages and suggests ways to improve their performance based on a set of rules for high performance web pages. YSlow is a Firefox add-on integrated with the Firebug web development tool' and is an app in the web browsers category. There are more than 10 alternatives to Yahoo! YSlow for a variety of platforms, including Web-based, SaaS, Google Chrome, Mozilla Firefox and Wordpress apps. The best Yahoo! YSlow alternative is Google Lighthouse, which is both free and Open Source. Other great apps like Yahoo! YSlow are GTmetrix, PageSpeed Insights, WebPageTest and Yellow Lab Tools.
Lighthouse is an open-source, automated tool for improving the quality of web pages. You can run it against any web page, public or requiring authentication. It has audits for performance, accessibility, progressive web apps, SEO and more.
GTmetrix is a free tool that analyzes your page's speed performance. Using Page Speed and YSlow, GTmetrix generates scores for your pages and offers actionable recommendations on how to fix them.
PageSpeed Insights (PSI) reports on the performance of a page on both mobile and desktop devices, and provides suggestions on how that page may be improved.
Run a free website speed test from around the globe using real browsers at consumer connection speeds with detailed optimization recommendations.
Use this free Website Speed Test to analyze the load speed of your websites, and learn how to make them faster.
Get the web's modern capabilities on your own sites and apps with useful guidance and analysis from web.dev.
Screpy is an AI-based web analysis tool that can analyze all pages of your websites in one dashboard and monitor them with your team. It's powered by Lighthouse and it also includes some different analysis tools (SEO, SERP, W3C, Uptime, etc).
Domsignal is an all-in-one platform dedicated to empowering developers, SEO experts, sysadmins, and security researchers in their quest for website excellence. We provide a comprehensive suite of tools to help you analyze and optimize your website's performance, security...
Boost your SEO, speed and security: Checkbot for Chrome crawls your site to test you’re following over 50+ best practices. Test 1,000s of pages in minutes for broken links, duplicate content, invalid HTML, insecure forms, redirect chains and more.
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