Email
DNS Blacklist Checker
Check whether an IP is listed on major email blacklists.
Queries public blacklists from our server. Free and rate-limited.
About this tool
Free DNSBL checker. Query the major email blacklists for an IP address and see whether it is listed, so you can fix deliverability problems at the source.
Frequently asked questions
What is a DNSBL?
A DNS blacklist is a public list of IP addresses associated with spam. Many mail servers reject or flag mail from listed IPs.
I am listed — what now?
Find out why (open relay, compromised account, shared IP) and fix the cause first, then request delisting from each list.
Can I check a hostname?
Yes, it is resolved to its IPv4 address before the blacklists are queried.
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