Question 1

What is a DNSBL (DNS Blacklist)?

Accepted Answer

A DNSBL (DNS-based Blacklist) or RBL (Real-time Blackhole List) is a list of IP addresses known to send spam. Email servers check incoming mail against these lists and may reject or flag messages from listed IPs. Major blacklists include Spamhaus, Barracuda, and SpamCop.

Question 2

How do I get delisted from a blacklist?

Accepted Answer

Each blacklist has its own delisting process. Generally, you need to: 1) Fix the underlying issue (compromised server, open relay, spam complaints), 2) Visit the blacklist's website and request removal, 3) Wait for the listing to expire (some auto-expire after 24-48 hours if no more spam is detected).

Question 3

Is this blacklist checker free?

Accepted Answer

Yes, completely free. We check your IP against 50+ blacklists using public DNS queries. No account required, no limits.

Blacklist Checker