SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Rank Math - Rank Math WordPress SEO plugin will help you rank higher in search engines. DOWNLOAD for FREE this plugin today to optimize your WordPress website for higher rankings and more traffic.
Lumar - (Previously DeepCrawl) Hosted SEO spider to analyze and find problems with websites.
The SEO Framework - Easy SEO for beginners, an awesome API for experts. WordPress SEO for everyone.
Website Checker Tech - WebsiteChecker.Tech is SaaS tool that detects SEO and availability issues of your website, making it easier for you to fix them.
Yoast SEO - Yoast SEO does everything in its power to please both visitors and search engine spiders.