Blocklist Checker

Check any domain and its mail server IPs against major DNS blocklists like Spamhaus, SpamCop, and Barracuda. Free, no account needed.

Domain to check

What is an email blocklist?

Blocklists (also called DNSBLs or RBLs) are databases of IP addresses and domains that have been reported for sending spam. Mailbox providers and spam filters query them in real time, so a listing on Spamhaus, SpamCop, or Barracuda can send your mail straight to spam or get it rejected outright.

What this checker does

Enter a domain and we resolve its A record and MX server IPs, then check the domain and each IP against high-signal DNS blocklists. You get a per-list verdict, the exact host that is listed, and the return code the blocklist published.

What to do if you are listed

Fix the root cause before requesting removal: secure compromised accounts, close open relays, and stop sending to addresses that complain. Then follow the delisting process on the blocklist operator's site. Most listings clear within a few days once the spam stops, and ongoing monitoring catches relistings early.

Frequently asked questions

Is this blocklist checker free?

Yes. Checking a domain and its mail server IPs against major blocklists is free, no account required.

Which blocklists do you check?

High-signal DNS blocklists that mailbox providers actually consult: Spamhaus ZEN, Spamhaus DBL, Barracuda, SpamCop, CBL, PSBL, Mailspike, and the Sender Score blocklist. We check your domain plus its A record and MX server IPs.

Does a listing always hurt deliverability?

Not equally. A Spamhaus listing is severe because major providers use it, while smaller lists have less impact. Treat any listing as a warning sign and investigate the cause.

How do I get delisted?

First stop the behavior that caused the listing, then submit a removal request on the blocklist operator's website. Some lists expire automatically within 24 to 48 hours once spam reports stop.