SemrushBot
Semrush's crawler, building the link and site-audit data behind one of the largest SEO platforms.
SemrushBot/7~bl; +http://www.semrush.com/bot.htmlOfficial documentation: www.semrush.com
What SemrushBot does
SemrushBot crawls for Semrush's backlink index and related datasets. Like AhrefsBot, it is high-volume, well-documented, and honors robots.txt and crawl-delay.
Why it visits your site
Commercial link-graph building; your site is inventory.
The bigger picture: SEO tool crawlers
SEO tool crawlers are commercial data harvesters with a twist: the product they build from your pages - link graphs, keyword data, authority metrics - is one your own marketing team may pay to use. They are consistently among the highest-volume non-search crawlers on the web, and they send you nothing directly. The trade is indirect: tolerate the crawl and the industry's measurement layer, including your own dashboards, stays complete.
These crawlers are generally well-behaved - documented, robots-compliant, honoring crawl-delay - so the decision is genuinely yours to make on resource and privacy grounds. Sites that block them typically do it to deny competitors easy backlink intelligence or to trim server load; sites that allow them are usually buying the completeness of their own tooling.
Should you block it?
The same trade as AhrefsBot: blocking trims server load and data exposure but breaks Semrush's view of your own site if your team relies on it.
Block via robots.txt
Add these lines to the robots.txt at your site root to ask SemrushBot to stay away:
User-agent: SemrushBot Disallow: /
Remember that robots.txt is a request, not a lock - compliance is voluntary, and enforcement happens at the server. Viz's AI Control pairs robots.txt rules with server-level 403 responses and then probes your site to verify the block is actually holding.
How to see SemrushBot traffic on your site
You have three windows onto it, each with a catch. Raw hosting access logs contain every SemrushBot request, but many managed WordPress hosts don't expose them, and when they do you are grepping text files by hand. A CDN dashboard sees the traffic at the edge, but it lives outside WordPress and speaks in totals, not in your site's terms. And JavaScript analytics - GA4 and friends - will never show it at all, because SemrushBot doesn't run scripts.
Viz's answer is the request log: filter to SemrushBot and read exactly which URLs it fetched and when, right inside wp-admin - then watch the same filter after any blocking decision to see whether the visits stopped, slowed, or kept coming.