Screaming Frog Screaming Frog comes in as an excellent tool that enables you to take one domain & crawl through its pages the same way any search engine does. Perhaps, it crawls via the pages on the website & pulls through almost everything you require to see that is relevant to its SEO performance. It is great for On-Page SEO as well. If you haven't used Screaming Frog for your technical SEO audits yet, start using it!
ISS SEO Toolkit This tool was developed by IIS; it also crawls a website from your desktop & creates a report right on the site. The IIS SEO Toolkit offers the user with a clear breakdown of the website's potential issues as well as suggests remedies for them.
SEMrush Site Audit Are you a SEMrush user? If yes, you would have surely heard of this tool and how effective it can be. On the other hand, if you are not a user yet, give it a go! This audit tool crawls a domain from your web browser & generates an online report in order to show where exactly potential issues are there and it also shows them in a very easy-to-read format along with export options meant for offline analysis & reporting. This tool is principally useful to spot when someone has perhaps made some unexpected changes to a website (of course, often with a good reason) that can probably end in negative SEO consequences.
Pingdom DNS Check Inaccurately setup DNS servers tend to cause downtime & crawl errors. The tool best used to check a site's DNS health is Pingdom Tools DNS tester. Well, it checks every level of a website's DNS & reports you of any errors or warnings in the setup. Using this tool, you can identify quickly anything at the DNS level, which would potentially cause crawl errors, website downtime, and usability problems.
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