Email Blacklist Check
Check an IP address or domain against widely used DNS blocklists, the lists mail servers consult to reject spam.
Free, no account needed.
What this check looks at
- For an IP address: IP-based blocklists such as Spamhaus, Barracuda, SpamCop and others.
- For a domain: its mail servers' IPs, plus domain-based lists that track domains seen in spam.
- Which list, if any, reports a listing, with a link to its removal process.
Listed? What to do
First find and fix the cause: a compromised account or server, a form that sends mail without checks, or mailing people who didn't ask for it. Then request removal through the list's own website. Most lists delist automatically once the problem stops, and requesting removal before fixing it usually leads to a quick relisting.
If you send through a shared service like SendGrid or Microsoft 365, a listing of their shared IP is theirs to resolve. Contact their support.
Frequently asked questions
Does one listing mean my mail is blocked everywhere?
No. Each receiving server chooses which lists to use. A Spamhaus listing affects many receivers; a small list may affect almost none.
Why is my new IP address already listed?
Some lists include whole ranges of residential or dynamic IPs, or IPs with a history of abuse by a previous owner. Request removal and explain that the address has changed hands.
Related tools
- SMTP Server TestConnect to a mail server on port 25 and check its greeting, STARTTLS support and TLS certificate, just as a sending server would.
- MX Record LookupSee which mail servers receive email for a domain, in priority order, with their IP addresses and reverse DNS.
- Email Deliverability TestSend one email to a unique test address and get a report on how it authenticates, exactly as a receiving server sees it.
- Reverse DNS (PTR) LookupFind the hostname an IP address points back to. Mail servers check this before accepting email.