Directory/Categories/SEO/MJ12bot/v2.0.4

MJ12bot/v2.0.4

GoodBotCommunity-sourced

A distributed web crawler operated by Majestic that maps link relationships to power a comprehensive backlink intelligence database. Operated by Majestic-12 Ltd.

Operator website ↗

GoodBot

Assessment

SEO

What is MJ12bot/v2.0.4?

MJ12bot is the primary crawler for Majestic, a UK-based search intelligence company that maintains one of the largest publicly available backlink databases. Unlike general-purpose search engines, it focuses specifically on mapping the hyperlink structure of the web to provide link intelligence for businesses and SEO professionals. The bot operates as a distributed system, utilizing a network of nodes to efficiently traverse the internet and update the Majestic Site Explorer index.

Helpful — It is a well-known, legitimate crawler used by SEO professionals and webmasters to analyze link profiles and site authority.

Identification

Bot name

MJ12bot/v2.0.4

Operator

Majestic-12 Ltd

Why it crawls your site

The bot crawls the web to build a comprehensive map of how websites are interconnected via hyperlinks. This data is processed to calculate metrics such as Trust Flow and Citation Flow, which are essential for SEO audits and competitive analysis. By continuously re-crawling pages, the bot ensures that the backlink index remains current, allowing site owners to monitor their own link profiles and identify potential technical issues or link-building opportunities.

IP ranges

Requests from MJ12bot/v2.0.4 originate from these published ranges. For strict verification, match the source IP against this list in addition to checking the user-agent and reverse-DNS.

Showing 24 of 68 ranges

Block or allow MJ12bot/v2.0.4

Block it

Add a Disallow rule for Mozilla/5.0 (compatible; MJ12bot/v2.0.4; http://mj12bot.com/) in your robots.txt file. You can also block at the server level using your web server configuration or CDN firewall rules to filter requests matching the user-agent string.

# Block MJ12bot/v2.0.4 from crawling your entire site
User-agent: Mozilla/5.0 (compatible; MJ12bot/v2.0.4; http://mj12bot.com/)
Disallow: /

# Allow MJ12bot/v2.0.4 full access
User-agent: Mozilla/5.0 (compatible; MJ12bot/v2.0.4; http://mj12bot.com/)
Allow: /