https://aioseo.com/seo-analyzer/
https://seomator.com/free-seo-audit-tool
https://www.thehoth.com/seo-audit-tool/
https://rankmath.com/tools/seo-analyzer/
https://backlinko.com/tools/seo-checker
https://www.workiz.com/tools/free-seo-audit-tool/
https://www.seobility.net/en/seocheck
https://zadroweb.com/seo-auditor
https://neilpatel.com/ubersuggest
https://seoimage.com/seo-tools
https://www.w3era.com/seo-tools/website-seo-analyzer
https://daniliants.ventures/seo-checker
https://sitechecker.pro/on-page-seo-checker/
https://www.serpwizard.com/free-seo-audit/
https://developers.google.com/search
https://www.wpbeginner.com/tools/seo-analyzer-tool/
https://medium.com/@www.ameerhanzalakhan/50-free-seo-audit-tools-for-your-website-f377ef0af70a
https://smallseotools.com/alexa-rank-checker
https://www.seoreviewtools.com/google-seo-checker/
https://www.sapbwconsulting.com/free-website-seo-grade-audit-serp-sem-amp
https://search.google.com/test/rich-results
https://home.snafu.de/tilman/xenulink.html
Dead Link Checkers:
https://www.deadlinkchecker.com
https://www.brokenlinkcheck.com
https://ahrefs.com/broken-link-checker
https://validator.w3.org/checklink
https://www.duplichecker.com/broken-link-checker.php
https://ettvi.com/broken-links-finder
https://dnschecker.org/website-broken-link-checker.php
https://www.powermapper.com/products/sortsite/checks/link-checker
https://w3speedup.com/tools/broken-link-checker/
https://www.duplichecker.com/broken-link-checker.php
https://seranking.com/broken-link-checker.html
https://www.seoreviewtools.com/broken-link-checker/
https://www.siteguru.co/free-seo-tools/broken-links
Security Audit:
https://pentest-tools.com/website-vulnerability-scanning/website-scanner
https://www.ssllabs.com/ssltest
https://owasp.org/www-community/Vulnerability_Scanning_Tools
https://www.sitelock.com/free-website-scan
https://www.immuniweb.com/websec
https://www.ssltrust.com/ssl-tools/website-security-check
https://developer.mozilla.org/en-US/observatory
https://www.upguard.com/webscan
https://hackertarget.com/drupal-security-scan
https://www.getastra.com/website-scanner
https://beaglesecurity.com/free-website-security-assessment
https://hogtheweb.com/free-website-security-scan/
https://service.h-x.technology/scan-monitor
https://www.isitwp.com/wordpress-website-security-scanner
https://secureweb.ma/free-website-scanner/
https://free.pentesttesting.com
Technical Tools:
SEO Tools:
https://business.google.com/us/ad-tools/keyword-planner
https://neilpatel.com/ubersuggest
https://seranking.com/keyword-suggestion-tool.html