Mail server blacklist checker.
Wondering is my IP blacklisted? This free IP blacklist checker runs a live RBL check on any IP or domain against 14 of the most-consulted mail blocklists — Spamhaus ZEN, Barracuda, SpamCop, SORBS, UCEPROTECT and more — in parallel, in seconds, straight from public DNS.
No signup · runs in your browser · also try our MX lookup, DNS lookup and SPF/DKIM/DMARC checker.
How to check if an IP or domain is blacklisted in 3 steps
- 1
Enter the IP or domain in the box above (e.g.
203.0.113.42orexample.com) and click Check blacklists. - 2
Read the verdict. We query 14 RBLs in parallel and flag any that list you — Listed shows the return code; Clean means that list has nothing on you.
- 3
Request delisting. Fix the underlying cause first, then use the direct delisting link beside each listing — most blocklists won't relist a host that's still misbehaving.
Major email blocklists we check
We check the lists mail receivers actually consult — not obscure ones nobody queries. These are the heavyweights; the tool tests 14 in total.
| Blocklist | Type | Why it matters |
|---|---|---|
| Spamhaus ZEN | IP (RBL) | The single most-consulted list — landing here means large swathes of the internet silently reject your mail. |
| Barracuda (BRBL) | IP (RBL) | Powers Barracuda email gateways used across enterprise and government; listing hits a big slice of inbound filtering. |
| SpamCop | IP (RBL) | Complaint-driven list consulted by many providers; listings expire automatically once spam stops, but recur if the source isn't fixed. |
| SORBS | IP (RBL) | Long-running aggregate list (spam, open relays, dynamic ranges) still queried by a meaningful share of receivers. |
What this checks
RBLs / DNSBLs
A DNS blocklist (RBL) is a database of IPs or domains that mail receivers consult to decide whether to accept your mail. If you land on a major one — Spamhaus ZEN especially — large chunks of the internet will silently reject you. We check the lists most commercial mail servers actually consult, not obscure ones nobody uses.
IP blacklists
For an IP, we check 14 popular IP-based blocklists in parallel. If you're listed on one, the result includes a direct link to that blocklist's removal/delisting page so you can start the request immediately.
URI/domain blacklists
For a domain, we also check Spamhaus DBL, SURBL and URIBL — the blocklists that mail servers consult for domains appearing in message bodies (links). Being on a URIBL doesn't block your mail server, but it does kill click-through on any campaigns you send.
Domain → IP resolution
Enter a domain, we resolve it to its A records and check each. The IP that actually sends your mail is what's listed — and that isn't always the IP your domain resolves to. For mail servers specifically, you usually want to check the IP your MX hostnames resolve to, not the apex domain.
Common reasons you get blacklisted
A blacklist check often surfaces a problem that's been quietly killing your deliverability. The causes we see most:
Compromised account or malware
A cracked mailbox or an infected machine on your network blasts spam through your server — RBLs catch it within minutes and list the sending IP.
Shared-IP neighbours
On shared hosting or a shared mail relay, one bad neighbour's spam burns the IP reputation for everyone on it — including you.
Missing SPF/DKIM/DMARC
Without aligned authentication, spammers spoof your domain and the abuse lands on your reputation. Run the SPF/DKIM/DMARC check →
Sudden volume spikes
A big unwarmed campaign or a runaway script that loops on send looks exactly like a spam run to a receiver — and trips automated listing thresholds.
Stuck on a blocklist? We get you delisted and keep you off.
Edos Solutions diagnoses the cause, fixes the source, requests delisting on every list you're on, and hardens your mail infrastructure so it doesn't happen again.
Listed somewhere?
If you're on Spamhaus or Barracuda, you have a deliverability problem right now and you need to fix it before requesting delisting — most blocklists won't relist a host that's still misbehaving. The usual causes: a compromised account sending spam, a misconfigured open relay, a forwarder leaking mail, or a shared-hosting neighbour burning the IP for everyone.
We do this work for clients every week — diagnose the cause, fix it, request delisting, and harden the system so it doesn't happen again. If you'd rather not chase your tail through forwarder logs and DKIM signatures yourself, we can take it from here.
Privacy
Lookups happen in your browser via Cloudflare's public DNS-over-HTTPS endpoint. Edos Solutions doesn't log the IPs or domains you check, doesn't run any analytics on this page, and doesn't capture your IP.
References
- Spamhaus, the IP and domain reputation blocklists.
- Spamhaus Blocklist Removal Center, how to request delisting.
Frequently asked questions
- What is a DNS blocklist (DNSBL / RBL)?
- A DNS blocklist is a real-time database of IP addresses or domains reported as spam sources, open relays, or malware distributors. Mail servers query these lists when a message arrives — if the sending IP is listed, the message may be rejected or junked. We check 14 of the most widely consulted blocklists including Spamhaus ZEN, SpamCop, Barracuda and SORBS.
- Why is my IP or domain blacklisted?
- The most common causes are: a compromised email account on your server sending spam; a misconfigured mail server acting as an open relay; a forwarder leaking third-party spam through your IP; or shared hosting where a neighbour's activity burns the IP for everyone. Spamhaus and Barracuda list IPs automatically based on complaint thresholds and spam trap hits — you don't get notified.
- How do I get delisted?
- Fix the underlying problem first — most blocklists won't delist an IP that's still misbehaving, and being relisted after removal is harder to reverse. Once the source is plugged, each listing in our results includes a direct link to that blocklist's delisting request page. Spamhaus ZEN can clear within hours; Barracuda takes 12–24 hours; some smaller lists have manual review queues.
- What is the difference between IP blacklists and URI blacklists?
- IP blacklists track the reputation of mail-sending servers. If your sending IP is listed, receivers reject or junk your mail at the connection level. URI blocklists (Spamhaus DBL, SURBL, URIBL) track domains appearing in message bodies as links — being on a URI blocklist doesn't block your mail server, but it kills click-through on any campaigns you send because receivers strip or warn about the links.
- Should I check my domain or my IP address?
- Both. The IP that sends your mail (the actual MX server IP) is what IP-based blocklists track. Your domain is what URI-based blocklists track. If you're troubleshooting deliverability, check the actual sending IP from your mail server's Received: headers, not just the apex domain — they're often different.
- How do I check if my IP address is blacklisted?
- Type your IP address (e.g. 203.0.113.42) into the box above and click "Check blacklists". This free IP blacklist checker queries 14 of the RBLs mail receivers actually consult — Spamhaus ZEN, Barracuda, SpamCop, SORBS, UCEPROTECT and more — in parallel, and tells you which ones list you with a direct link to each delisting page. The lookups run in your browser; nothing is logged. If you only know your domain, enter that instead and we'll resolve it to its sending IPs and check each one.