SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Index Buddy by GSoftwareLab - All of your backlinks will be quickly indexed! Index Buddy makes backlink and domain indexing simple and quick.
Lumar - (Previously DeepCrawl) Hosted SEO spider to analyze and find problems with websites.
Google Structured Data Testing Tool - Google Structured Data Testing Tool
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.
Google SERP Snippet Optimization - SEOmofo tool replicates the appearance of a snippet in Google SERPs, which allows SEOs to optimize a page title and description for maximum click-through rate.