Privacy & security
IP blacklist check
See whether an IP address or mail server appears on popular spam blocklists.
Check
What is an IP blacklist?
Email providers use DNS-based blocklists (DNSBLs, also called RBLs) to spot senders of spam. If a mail server's IP address is listed, emails from it may be rejected or land in the spam folder. Lists also include hacked computers, open proxies and addresses that should never send email directly, such as home connections.
My IP is listed – what now?
- Home or mobile IP? This is common and usually harmless – these addresses are listed because home connections shouldn't send email directly. It does not affect normal browsing.
- Your mail server? Find out why it was listed: check for compromised accounts, open relays or infected devices, and fix the cause first.
- Then follow the removal (delisting) link on the blocklist's website. Many lists remove entries automatically after some time.
Blocklists are run by independent organisations; we just show what they report.
How to read the blacklist results
For each blocklist the checker shows one of three states:
- Not listed – the list has no record for this IP. This is what you want to see everywhere.
- Listed – the list returned a match, often with a reason code or text explaining why and a link to its removal page.
- Error or timeout – the list did not answer in time or refused the query. That is not a listing; try again later.
Not all lists carry the same weight. A listing on a major list used by many mail providers can stop most of your email being delivered. A listing on a small, aggressive or rarely used list may have no visible effect at all. Look at your bounce messages: they usually name the list that caused the rejection.
Common reasons an IP gets listed
- A compromised device or account sending spam – a hacked mailbox password, an infected PC on your network, or a vulnerable website contact form.
- Missing or generic reverse DNS. Mail servers without a proper PTR record, or with a name like
dynamic-203-0-113-7.provider.net, look like home computers. Check yours with our reverse DNS lookup. - Dynamic or residential address ranges. Some lists include every home broadband IP on purpose, because legitimate mail servers should not send from them. This is normal for a home connection and not caused by you.
- Bad neighbours. On cheap hosting, a whole range can be listed because of other customers.
- Sending to old or purchased mailing lists that hit spam traps.
Before you request removal
Fix the cause first – otherwise you will simply be listed again, and some lists make repeat removals slower. Change passwords on affected mailboxes, scan your network for malware, make sure your mail server is not an open relay, and set up SPF, DKIM and DMARC (you can verify them with our DNS lookup). Our full guide, Why is my IP blacklisted?, walks through each step and how removal works on the major lists.
IP blacklist check – frequently asked questions
How long does a listing last?
It depends on the list. Some remove an IP automatically after a day or a week without new spam; others need you to submit a removal request after fixing the problem.
Will a blacklist affect my website?
Spam blocklists mainly affect email. A few security services also use reputation lists to block or challenge visitors, so a badly listed server IP can occasionally cause CAPTCHAs for your site.
Can I pay to be removed?
Reputable lists offer free removal once the problem is fixed. Be careful with services that charge for “guaranteed delisting”.