Google Mobile Test: https://search.google.com/test/mobile-friendly
Google Speed Test: https://developers.google.com/speed/pagespeed/insights/
Structured Data Testing Tool (Sunset): https://search.google.com/structured-data/testing-tool/
Google Rich Results Test: https://search.google.com/test/rich-results
Google Structured Data Markup Helper: https://www.google.com/webmasters/markup-helper/u/0/
Sucuri Site Check: https://sitecheck.sucuri.net/
Built With: https://builtwith.com/
Search Engine Market Share: https://gs.statcounter.com/search-engine-market-share
Industry-leading accuracy for image understanding: https://cloud.google.com/vision
Google-My-Business changes timeline: https://searchengineland.com/library/google/google-google-my-business
Address verification: https://www.edq.com/free-address-lookup-tool/
USPS tool: https://tools.usps.com/zip-code-lookup.htm?byaddress
Keyword Sheeter: https://keywordsheeter.com/
Answer the public: https://answerthepublic.com/
Zoho Support Plans: https://www.zoho.com/crm/resources/support-plans.html
Your Digital Marketing Tool Box: https://www.thinkwithgoogle.com/tools/
KML File maker and GeoSiteMap.xml: https://www.geositemapgenerator.com/generate
Google My Business Categories by Blumenthal: https://blumenthals.com/google-lbc-categories/
Screaming Frog SEO Spider: https://www.screamingfrog.co.uk/seo-spider/
TopVisor Keyword tool: https://topvisor.com
Moz Link Explorer: https://moz.com/link-explorer
Majestic Site Explorer: https://majestic.com/reports/site-explorer
Ahrefs Backlink Checker: https://ahrefs.com/backlink-checker
Bright Local Local Search Checker: https://www.brightlocal.com/local-search-results-checker/