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Blocklist Checker
Email blocklists (DNSBLs) list IPs and domains seen sending spam; being on one can send your mail straight to spam or get it rejected. This checker queries the major lists at once, Spamhaus (via a live DQS key), SpamCop, Barracuda, UCEPROTECT, PSBL, Mailspike, SURBL, URIBL and others. Enter an IP, or a domain to check both the domain and its sending IP.
Blocklist Checker, FAQ
What is an email blocklist (DNSBL)?A DNSBL (DNS-based blocklist) is a published list of IP addresses or domains associated with spam. Receiving mail servers query these lists in real time to decide whether to accept, flag, or reject a message.
Why is my IP or domain blacklisted?Common causes are sending spam (even unknowingly via a compromised account), poor IP reputation inherited from a shared range, an open relay, or hitting spam traps. Fix the root cause before requesting delisting.
How do I get removed from a blocklist?Each list has its own delisting process on its website. Remove the underlying problem first, most lists re-list quickly if the bad behaviour continues, and some auto-expire once it stops.
Want the complete picture? The Deliverability Radar scores a domain or IP out of 100 across DNS, authentication, reputation and connectivity, and emails you a branded PDF.
More free tools: SPF Checker · DMARC Checker · DKIM Checker · MX Lookup · Reverse DNS Lookup · MTA-STS Checker · DNS Lookup · Blocklist Checker
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