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Spam blacklist check (DNSBL)
Enter an IP or a domain — we will resolve the IP and check it against popular blacklists.
Results
What it is
DNSBL (DNS‑based Blackhole List) are DNS zones that list IP addresses seen as sources of spam or suspicious activity. Checks are done via DNS queries.
How it works
We mirror the reference site's list of blacklists and perform parallel DNS queries for your IP. If you enter a domain, we resolve its A record (IPv4) and check that address.
Limitations & notes
Being listed does not always mean active spamming. It may be due to open relays/proxies or infections. To delist, visit the blacklist's website and follow their instructions.