Domain And IP Blacklist Checker.

Yes. Blacklist, blocklist, DNSBL and RBL all name the same thing: a list of IP addresses or domain names, published in DNS, that mail servers query to decide whether to trust a sender. Lists of IP addresses are usually called DNSBLs and lists of domains are often called URI or domain blocklists. RFC 5782 describes how both are queried.

Because a list that did not answer properly has told us nothing about you. Some lists refuse queries and answer with a special refusal code, some time out, and some have shut down. Before trusting a list's answer, the checker looks up the test entries every list must publish under RFC 5782. A list that fails them, or refuses, is marked Not Checked with the reason and a link to its own lookup.

Spamhaus, URIBL and SURBL allow free lookups only for non-commercial use. Where this checker has no commercial access to one of them, it marks that list Not Checked and links to the list's own free lookup page, where you can check your domain or address directly. It never shows a list it could not query as clean.

Fix the cause first, then use the removal link next to the listing. Most lists list an address again quickly if the cause is still there. Removal works differently on each list: SpamCop listings expire on their own 24 hours after the last spam report, anyone can remove an address from PSBL instantly, and other lists take a request through their own site. Each listing on this page says how removal works for that list.

Blacklists are one signal among several. Gmail, Outlook and Yahoo do not publish public blacklists and decide mostly from their own reputation data, authentication and complaints. Gmail asks bulk senders to keep the spam rate reported in Postmaster Tools below 0.3%. Check your SPF, DKIM and DMARC records, and test where a real message lands at each provider.

Not to you. Those servers are shared by many customers, and a listing on one of them is the provider's to handle. What you control is your domain's reputation and any server you name yourself in SPF, so the checker marks listings on shared provider servers as context rather than problems. To find the exact address that sent one message, read that message's headers.

An IP blacklist lists the addresses of servers that sent spam, so it affects everyone sending from that server. A domain blacklist lists domain names seen in spam, in the From address or in links, so it follows you to any server you use. A domain listing cannot be fixed by changing mail provider, which is why it usually matters more for cold email.

We keep the domain or address you checked and the result for 90 days, with your IP address and browser, to prevent abuse. For an email address we keep only the domain. To check a list, a DNS query for the domain or address goes to that list's operator, which is how every blacklist lookup works.

Check before a new campaign, after a sudden drop in replies or a rise in bounces, and after any change to the servers you send from. Listings can appear and expire within a day: a SpamCop listing ends 24 hours after the last report. One check shows the lists as they answered at that moment.