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 * [ISP.Tools](https://www.isp.tools) - Is a free platform offering network diagnostic tools (ping, traceroute, MTR, DNS, WHOIS, HTTP, etc.) tailored for ISPs and infrastructure professionals.
 * [Kloth](http://www.kloth.net/services)
 * [Majestic](https://majestic.com) - Find out who links to your website.
+* [Mark Monitor WHOIS](https://whois-webform.markmonitor.com/whois/) - Displays domain registration information.
 * [MaxMind](https://www.maxmind.com)
 * [MetaDefender](https://metadefender.com) - Threat analysis service for URLs, files, certificates, domains, and suspicious hashes.
 * [Netcraft Site Report](http://toolbar.netcraft.com/site_report?url=undefined#last_reboot) - is an online database that will provide you a report with detail information about a particular website and the history associated with it.