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Blacklist Check

Check an IP address or domain against 60+ DNS-based blacklists (RBL/DNSBL) in real time.

About the Blacklist Check

DNS-based blacklists (DNSBLs or RBLs) are the reputation lists that mail servers consult before accepting a message. If one of your sending IPs or your domain is listed, your mail may be rejected or sent to spam by a large share of receivers. This tool checks an IP address or a domain against more than 60 lists in parallel — IP lists such as Spamhaus ZEN, SpamCop, Barracuda, PSBL and UCEPROTECT, and domain/URI lists such as Spamhaus DBL, SURBL and URIBL.

When you enter a domain, we also resolve its web and MX addresses and check each of them. Every listing shows the reason code translated into plain language and a link to the operator’s delisting page.

Reading the result

  • Listed — the operator returned a listing code. Fix the cause before requesting removal or you will be re-listed.
  • Clean — not listed on that list right now.
  • Timeout — the list did not answer in time; this is not a listing.

Listings change hour by hour. Monitor your IPs to be alerted the moment you are listed — and when you come off.

Monitor this automatically

Get alerted when this check starts failing, when you land on a blacklist or when a certificate or domain is about to expire.

Start free monitoring