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Enter a domain or IP address to check it against major email blacklists.
Free, no signup. Up to 10 checks per hour.
Blacklists, also called blocklists or DNSBLs, are lists of IP addresses and domains linked to spam. Mail servers query them over DNS for every message they receive.
IP lists such as Spamhaus ZEN, SpamCop and Barracuda hold the addresses of servers that sent spam. A listing on the IP that sends your mail can get it rejected or filtered.
Domain lists such as Spamhaus DBL and URIBL hold domains seen in spam, checked against the sender address and the links in a message.
Not listed means the list has no entry for that address right now. Could not check means the list refused or did not answer our query, which says nothing either way.
For a domain we also check the IPs of its MX servers. Those receive mail. If you send through Google Workspace or Microsoft 365, your sending IPs are shared and managed by the provider.
Find and fix the cause first: a hacked account or website, a bought list, or mail sent to old addresses that became spam traps. Most lists relist quickly if the problem continues.
Then use the removal page shown for each list. Some, like SpamCop and UCEPROTECT Level 1, expire on their own once the spam stops.
Warm up new mailboxes and watch SPF, DKIM, DMARC and blacklists for every inbox you connect. See Email Warmup
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Enter the domain or the IPv4 address above. We query each blocklist over DNS the same way mail servers do and show which ones list it, with a removal link for each listing.
The IP that sends your mail. Send a message to another account, view the original headers, and find the IP in the Received line where the receiving server logged who connected to it. For Google Workspace or Microsoft 365, that IP is shared and the provider handles its reputation.
It depends on the list. A Spamhaus listing often leads to rejected mail because many servers use it, while UCEPROTECT has much less effect. Large mailbox providers such as Gmail rely mostly on their own reputation data.
SpamCop listings expire about 24 hours after the reports stop, and UCEPROTECT Level 1 after seven days. Lists with a removal form, such as Spamhaus and Barracuda, act after you fix the cause and submit a request.
The list refused our query or did not answer in time. Some lists limit free lookups, so this is not a listing. Check that list on its own website to be sure.
SORBS shut down in June 2024 and no longer publishes listings. Any tool that still reports a SORBS result is out of date.
