Email Blacklist Checker
Check if your email sending IP or domain is listed on major DNS blacklists. Being blacklisted can severely impact deliverability and inbox placement.
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DNS Blacklists and Email Deliverability
DNS-based blackhole lists (DNSBLs) are databases of IP addresses and domains known for sending spam. Major ISPs including Gmail, Outlook, and Yahoo use DNSBLs as one of many signals when deciding whether to deliver an email to the inbox, route it to spam, or block it entirely.
Being listed on a DNSBL does not automatically mean your emails will be blocked — different ISPs use different blacklists with different weighting. However, being listed on Spamhaus ZEN, Barracuda, or SpamCop is a strong negative signal that will almost certainly affect deliverability.
Use this checker alongside our Deliverability Calculator and Sender Reputation Checker to get a complete picture of your deliverability health. For ongoing monitoring, see our Authentication Health Check.