Free SEO Checker by Spotibo - An SEO checker that analyses based on Google's algorithm 👀
Smaller - Make your websites load faster
SEO Analyzer By Neil Patel - A free SEO analyzer for your site
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Curatedseotools.com - Curated directory of the best SEO tools.
Checkbot - Checkbot will boost the SEO, speed and security of your site by checking you're following 50+ web best practices. Browser extension with free and paid plans.