How to Use the Email Blacklist Check
Enter an IPv4 address or a domain and read one row per list and target, with unavailable lists kept apart from clean results.
- Enter the IPv4 address of your sending server, or your domain to check it together with its mail servers.
- Select Check blacklists and wait while each list’s test entry and your targets are queried.
- Review listed and unavailable rows, export the table as CSV and follow the removal link of any list that names you.
What the Email Blacklist Check Covers
The email blacklist check queries public DNS blocklists for your sending IP addresses and your domain, and it counts how many lists actually answered.
Email Blacklist Check by IP
For an IPv4 address the tool reverses the octets and queries each IP list, so 192.0.2.25 is looked up as 25.2.0.192 under the list’s zone, as RFC 5782 describes. An answer in 127.0.0.0/8 means listed, and the row shows the documented meaning of the return code. No record means the list does not include the address.
Check Domain for Email Blacklist
A domain is queried on the domain blocklists, which track domains seen in spam links and sender addresses. The tool also resolves the domain’s MX hosts and its own A record and checks up to four of those IPv4 addresses on the IP lists. Enter a mail server IP on its own to check one that was skipped.
Email Blacklist List
The checker queries 9 IP lists and 4 domain lists, each stored with its zone and removal page. Before trusting a list, it looks up the list’s permanent test entry, so a list that does not answer through Cloudflare DNS is marked unavailable instead of clean. Some lists, Spamhaus and URIBL among them, refuse public resolvers by design.
Email Blacklist Removal
Each listed row links to the list’s own page, where its removal process is described. Many lists expire entries automatically once the spam stops, while others need a request after you fix the cause. Asking for removal before fixing a compromised account or open relay usually leads to a quick relisting.
Blacklist Email vs Blacklist Domain
An IP blacklist judges the server that sends the mail, while a domain blacklist judges the domains named inside it.
| List type | What is listed | How it is queried | Typical reason |
|---|---|---|---|
| IP blacklist (DNSBL) | IP addresses of sending servers | Reversed IPv4 octets under the list zone | Spam, spam-trap hits or infected hosts on that IP |
| Domain blacklist (URI or RHSBL) | Domains in links and sender addresses | The domain name under the list zone | Domains advertised in spam, phishing or malware |
Frequently Asked Questions
What Does Email Blacklist Mean?
An email blacklist, also called a blocklist or DNSBL, is a published list of IP addresses or domains linked to spam or abuse. Mail servers query these lists while receiving mail and reject or filter messages that match.
What Happens When Your Email Is Blacklisted?
Receivers that use the list reject your messages with a bounce that often names the list, or quietly route them to spam. The impact depends on the list, because mailbox providers rely on some lists and ignore others.
How Do You Get Off an Email Blacklist?
Find and stop the cause first, such as a compromised account, an infected device or sending to old, unconfirmed addresses. Then follow the removal process on the list’s page, which this check links in every listed row.
How Do You Avoid an Email Blacklist?
Send only to recipients who asked for your mail, remove bouncing addresses and secure every account that can send. Authenticate your domain with SPF, DKIM and DMARC, and keep forward-confirmed reverse DNS on your sending IPs.
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