RBL / Blacklist Checker
Run an RBL check on an IP or domain: is it listed on the email blacklists that Gmail, Outlook and corporate filters consult? Spamhaus, Barracuda, SpamCop and five more, queried in parallel. The quickest domain reputation check for mail.
Frequently asked questions
How do I run an RBL check?
Enter an IP address or a domain above. The checker reverses the IP and asks each of 8 DNS blacklists (Spamhaus ZEN, Barracuda, SpamCop, SORBS, CBL, UCEPROTECT and two more) whether it is listed, all in parallel. Each list answers listed, clean or timed out.
Is this a domain reputation checker?
For mail, yes in the sense that matters most: whether the address your domain resolves to sits on the blacklists receivers consult. A domain is checked by its A record; to test the server that actually sends your mail, enter its outbound IP (the one in the Received headers or your ESP dashboard).
What happens if my IP is on a blacklist?
Receivers that use the list reject or spam-folder mail from that IP. Find and stop the cause first (a compromised account, an open relay, a bad mailing list), then request delisting on the list's own site. Spamhaus and Barracuda delist on request; some lists expire entries on their own.
Why is my IP listed when I never sent spam?
Shared and residential ranges are often listed as a whole (Spamhaus PBL, UCEPROTECT levels), and a previous owner of the IP may have spammed. On shared hosting or an ESP, the provider handles delisting. One listing on a minor list rarely affects delivery; Spamhaus, Barracuda or SpamCop listings do.