How to block OnCrawl Mobile
Operated by Oncrawl. OnCrawl Mobile is an SEO crawler operated by Oncrawl, a technical SEO platform. This mobile variant crawls websites to collect data and analyze site structure, performance, and other SEO-related metrics for website optimization purposes.
nginx
In the server block, then reload.
# In the server block. 403 rather than 444: a closed connection tells the
# operator nothing, and an agent that gets a status code can log it.
if ($http_user_agent ~* "(OnCrawl Mobile)") {
return 403;
}
Apache
In .htaccess or the vhost.
BrowserMatchNoCase "OnCrawl Mobile" bad_bot
<RequireAll>
Require all granted
Require not env bad_bot
</RequireAll>
Cloudflare
Security → WAF → Custom rules.
# Security → WAF → Custom rules, action: Block (http.user_agent contains "OnCrawl Mobile")
WordPress
A child theme's functions.php, or a small plugin.
// functions.php of a child theme, or a small plugin. Runs before WordPress
// builds the page, so a blocked agent costs one PHP process and no queries.
add_action('init', function () {
$agent = $_SERVER['HTTP_USER_AGENT'] ?? '';
foreach (['OnCrawl Mobile'] as $needle) {
if (stripos($agent, $needle) !== false) {
status_header(403);
exit('Blocked: OnCrawl Mobile');
}
}
});
A rule on the user agent is a rule on a string it chose
The server rules match on a header the requester sets, which stops the agent that says who it is and not the one that copies somebody else's name. Botscope verifies identity against DNS and published address ranges, records which check decided each request, and shows you the ones that lied.