What is MJ12bot?
MJ12bot is Majestic's crawler. It maps the link relationships between websites for the data served at Majestic.com, using a distributed, community-run crawler.
Last verified 2026-09-30 against the operator's documentation. All bots
MJ12bot at a glance
- Operator
- Majestic
- Type
- SEO and link-index crawlers
- Purpose
- Maps links between websites for Majestic's link index.
- robots.txt token
MJ12bot- How to verify
- Majestic's crawler is distributed and uses no fixed IP blocks. Majestic offers a site-specific identification string instead.
- Operator documentation
- https://mj12bot.com/
How often is MJ12bot impersonated?
Majestic publishes no way to check a request that claims to be MJ12bot, so we cannot say which claims are false and show no share.
This directory measures requests between 3 July 2026 and 28 September 2026. The fake crawler report covers its own, earlier window (late June to 21 September 2026), so its figures differ from the ones here. Read it for the method.
Have a request that claims to be MJ12bot? Check its IP address.
Should you block MJ12bot?
- Allow it if
- you or your partners use this tool's backlink or audit data, or the crawl load is not a concern.
- Block it if
- the crawl load is noticeable and you have no use for the tool's data. Blocking it does not affect search rankings.
- What blocking changes
- Majestic stops crawling your site for its link index.
To block it, add this group to your robots.txt. Majestic says MJ12bot obeys robots.txt and Crawl-delay up to 20 seconds.
User-agent: MJ12bot
Disallow: /robots.txt only asks. It does nothing against a client that ignores it or only pretends to be MJ12bot. Stopping those takes verification at your edge.
MJ12bot: common questions
See which bots reach your site, and which of them are who they claim to be.
What is MJ12bot?
MJ12bot is Majestic's crawler. It maps the link relationships between websites for the data served at Majestic.com, using a distributed, community-run crawler.
How do I verify that a request is really MJ12bot?
Majestic's crawler is distributed and uses no fixed IP blocks. Majestic offers a site-specific identification string instead. The user agent alone proves nothing: any client can send it.
How do I block MJ12bot in robots.txt?
Add a group for User-agent: MJ12bot with Disallow: /. Majestic says MJ12bot obeys robots.txt and Crawl-delay up to 20 seconds. robots.txt only asks. A client that ignores it, or pretends to be MJ12bot, has to be stopped at your edge.
What happens if I block MJ12bot?
Majestic stops crawling your site for its link index.
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