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Is this IP on any blacklist?

Paste an IP or hostname — we'll query 10 DNSBLs (Spamhaus, Barracuda, SpamCop, SORBS, DroneBL, PSBL, Manitu, Interserver, CBL) plus AbuseIPDB, IPQualityScore and VirusTotal in one shot.

Try:
Checking — looking up…

Why check?

Mail delivery
If your outbound relay is on Spamhaus or Barracuda, Gmail and Outlook will junk or bounce every message.
Reputation drift
IPs get listed silently after a compromise, misconfigured DKIM, or noisy neighbor on shared hosting.
Debug rejections
Getting 550 5.7.1 or REJECT_RBL? This tells you exactly which list flagged you and where to file a delisting.
Before you migrate
Check a new VPS IP before you point mail at it — a dirty IP is a hard problem to see coming.

One check tells you now. Duck Stats tells you the moment it changes.

Add an IP or domain to Duck Stats and we'll sweep every DNSBL daily. Get an email the second a listing appears — not weeks later, when your mail is already bouncing.

See pricing → Monitor free →