Domain Blacklist Check
Verify if a domain or IP appears on spam or security blacklists
Enter a domain or IPv4 address to check against common DNS-based blacklists (DNSBL).
No blacklist check yet
Enter a domain or IPv4 address above, then click Check Blacklists to query common DNSBL providers and view the results here.
Learn more & FAQ
What does a blacklist checker do?
Mail servers and spam filters consult DNS-based blacklists (DNSBLs) before accepting a message - if the sending IP or domain appears on one, the message can be rejected or marked as spam without you ever knowing why. This tool queries a range of well-known DNSBL providers at once and tells you exactly which ones, if any, have your domain or IP listed.
How to read your results
Each blacklist provider checked is shown with a clean or listed status. A listing links through to that provider's own site, where you'll find the specific reason for the listing and a delisting process. If every provider comes back clean but you're still seeing deliverability issues, the cause is more likely SPF/DKIM/DMARC misconfiguration than a blacklist - the Email Security tools below check exactly that.
Frequently asked questions
What is a DNSBL blacklist?
A DNS-based blacklist (DNSBL) is a list of IP addresses or domains known or suspected to send spam or engage in other abuse. Mail servers and spam filters query these lists in real time and use a match to reject or flag incoming messages.
Why is my IP or domain on a blacklist?
Usually because mail sent from that IP triggered spam complaints, the IP was previously used by someone else for spam, a misconfigured mail server relayed unwanted mail, or - on shared hosting - another tenant on the same IP caused the listing.
How do I get removed from a blacklist?
Each blacklist operator runs its own delisting process, usually a web form on their site once you've fixed the underlying issue (open relay, compromised account, spam complaints). This tool tells you which lists you're on so you know exactly where to submit a removal request.
Does a blacklist listing affect anything besides email?
Most DNSBLs are specifically about email reputation, but some security and firewall products also consult IP reputation lists, so a listing can occasionally affect general network trust as well as mail delivery.
How often should I check my domain or IP?
Checking periodically, especially right after setting up a new mail server or noticing deliverability problems, catches listings early - before they cause a noticeable drop in email reaching recipients' inboxes.