Is My IP or Domain Blacklisted? How to Check and Get Delisted
A blacklist listing rarely hurts your Google rankings, but it can send your email to spam. Here is how a lookup works, why IPs get listed, and the order to fix it in.
The short answer
A blacklist (more exactly a DNS blocklist, or DNSBL) is a list of IP addresses that mail servers and firewalls use to decide whether to trust traffic. To check whether you are on one, take the IP address your domain or mail server uses and look it up on each list. If a list returns a match, you are listed. If it answers "no such record", you are not.
For a website, the address that matters is the one your domain resolves to. A listing there mostly affects email sent from that address, and anything that blocks listed IPs. It is not a Google ranking factor.
Enter a domain or IP and CheckSEO checks it against Spamhaus ZEN, SpamCop, Barracuda, SORBS and CBL in one pass, free and without signup.
Run the Blacklist CheckerHow a blacklist lookup works
Every list publishes itself as a DNS zone. You reverse the four numbers of the IP, add the zone name, and ask for that name. For the IP 203.0.113.7 and the zone zen.spamhaus.org, the name to look up is 7.113.0.203.zen.spamhaus.org. An answer in the 127.0.0.x range means listed, and the last number says why. "No such record" (NXDOMAIN) means not listed.
You can do this by hand with dig +short 7.113.0.203.zen.spamhaus.org, but you would repeat it for every list, which is why most people use a checker.
Why your IP gets listed
- A compromised site or mailbox. A hacked contact form, plugin or email account starts sending spam from your server, and reports build up.
- A noisy neighbour. On shared hosting, one abusive site can get the whole IP listed, and you pay for it without doing anything wrong.
- A residential or dynamic address. Some lists, such as Spamhaus PBL (part of ZEN), cover ranges that are not meant to send mail directly. Mailing straight from a home or office connection triggers them.
- A new IP with no history. A fresh address that suddenly sends in volume looks the same as a spammer's.
- Mail that people report. Lists such as SpamCop are driven by user reports, so a bulk mailing that recipients mark as spam can get an address listed.
A result of 127.255.255.254 is not a listing
Spamhaus and CBL do not answer queries that arrive through some large public DNS resolvers. Instead of a real result they return an address in 127.255.255.x, usually 127.255.255.254, which means "your query was refused". It says nothing about whether the IP is listed. If you check by hand through a public resolver and see that address on a clean IP, repeat the check from a resolver of your own, or use the list's own lookup page.
How to get delisted
Fix the cause first
Scan the site for malware, update plugins, rotate mail and hosting passwords, and read the outbound mail log to see what was sent. A listing that is removed before the cause is fixed comes back.
Find out which list flagged you
Run the check and note exactly which lists show a match, and the return code if you can. The code tells you the reason, and the delisting steps differ by list.
Request removal on that list's own site
Each list has its own removal form or lookup page. Search for the list name plus "delisting". Ask once, say what you fixed, and avoid repeated requests, which slow things down.
Check again after a day or two
Some listings are removed within hours and others age out when reports stop. Re-run the check, and if the IP is on shared hosting, ask your host to move you or deal with the abusive neighbour.
Blacklists and SEO
A DNSBL listing does not remove a site from Google. Its real costs are email landing in spam and some corporate networks blocking the address. Do not confuse it with a Google security warning: that appears in Search Console under Security issues, and it is a separate problem with a separate review process. If your site shows a browser warning rather than failing email, look there first.
Alongside the blacklist check, it is worth confirming that your mail authentication is in place. The SPF, DKIM and DMARC guide covers it, and the DNS lookup tool shows what your domain publishes.
Frequently asked questions
How do I check if my IP is blacklisted?
Look the IP up on each DNS blocklist: reverse its four numbers, add the list's zone name, and query it. A 127.0.0.x answer means listed and no such record means clean. A checker does this across several lists at once, and for a domain it first finds the IP the domain points to.
Does being blacklisted hurt my Google rankings?
Not directly. These lists are used to filter email and network traffic, not to rank pages. The usual damage is outbound email going to spam and some firewalls blocking the address.
Why does a clean IP show as listed on Spamhaus?
Spamhaus refuses queries from some large public DNS resolvers and returns 127.255.255.254, which means the query was refused. It is not a listing. Check again from your own resolver or on Spamhaus's own lookup page.
How long does delisting take?
It depends on the list. Some remove an address within hours of a request, and report-driven lists drop it once the reports stop. If the cause is not fixed, the listing usually returns.
Check your own site with the Blacklist / Spam Checker.
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