Blacklist checker
See if a domain or IP is on major email blacklists.
If your sending domain or mail-server IP lands on a blacklist (DNSBL), your email starts going to spam or bouncing. Enter a domain or IP to check it against major blocklists — Spamhaus, SpamCop, and Barracuda — and see exactly where it stands.
Frequently asked questions
What do I do if I'm listed?
Find and fix the cause (compromised account, bad sending practices, shared-IP neighbor), then request delisting on the blocklist's site. Most have a removal form.
Can you watch this automatically?
Yes — SJ Monitor checks your domain or IP daily against the major blocklists (hourly on our top plan) and alerts you when it appears, so you can act before deliverability tanks. Blacklists update over hours, not seconds, so a daily check catches listings without hammering the blocklist providers.
Why am I on a blacklist when I haven't spammed?
Common causes are a compromised account or device sending without your knowledge, a misconfigured mail server acting as an open relay, or sharing an IP range with a bad neighbor. Some lists also flag dynamic or residential IPs by policy.
How long does delisting take?
It varies by list — some remove automatically after the bad activity stops, others process a manual request in hours to a few days. Delisting only sticks if you've actually fixed the root cause first.
Should I check my domain or my IP?
Both. Domain-based blocklists (like SURBL/URIBL) flag the domains appearing in message bodies, while IP-based DNSBLs flag the sending server's address. A clean reputation needs both to be clear.
Does one listing mean my mail will bounce?
Not always — receivers weight blocklists differently, and a single minor listing may only nudge you toward spam. A listing on a major list like Spamhaus, however, can cause outright rejections, so treat it urgently.
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