Blocklist check
Check whether your mail server's IP address is on a public blocklist (blacklist), such as Spamhaus, SpamCop or Barracuda. Enter a domain to check domain blocklists.
How it works
A blocklist (or blacklist) is a public list of IP addresses or domains that have sent spam or look unsafe. Many receiving mail servers check them before accepting a message. If your server's IP is listed, your mail may bounce or land in spam.
Each list is checked with a DNS query, as RFC 5782 describes. A listing comes with a code that says why, which we translate where the list documents it, and often a short reason with a link. Domain lists (Spamhaus DBL, URIBL, SURBL) check domains as they appear in links inside emails.
Some lists, including Spamhaus, refuse queries from big shared DNS resolvers like ours. We then say we couldn't check, never that you're clean. Open that list's row in the results to check on its own site.
Before asking for removal, fix the cause: a hacked account or computer, an open relay, or mail to old or bought address lists. Otherwise the listing comes back. A missing PTR record can also get an IP listed.