Moz - Backed by industry-leading data and the largest community of SEOs on the planet, Moz builds tools that make inbound marketing easy.

WebsiteSpeedAnalysis.com - Website Speed Analysis Tool

Ahrefs - Ahrefs is a toolset for SEO and marketing. We have tools for backlink research, organic traffic research, keyword research, content marketing & more. Give Ahrefs a try!

GTmetrix - GTmetrix is a free tool that analyzes your page's speed performance. Using PageSpeed and YSlow, GTmetrix generates scores for your pages and offers actionable recommendations on how to fix them.

Serpstat - Search analytics, Rank tracking, Backlink analysis and Site Audit tool.

PageSpeed Insights - PageSpeed is addon for ...