What Is an IP Blacklist Check?

An IP blacklist check tells you whether an IP address or domain appears on common spam and abuse blocklists. Being listed can cause email delivery failures, CAPTCHA challenges, or rejected requests. Checking reputation helps you diagnose issues and decide whether to remediate, delist, or change infrastructure.

How to use this IP Blacklist Checker

  1. Enter an IP address or domain.
  2. Click Check Blacklist.
  3. Review whether the target is listed and which databases report it.

Blacklist Databases

Spamhaus
SORBS
Barracuda
SpamCop
Invaluement
UCEPROTECT
DNSBL.info
PSBL
NJABL
RBL

Frequently Asked Questions

What is an IP Blacklist?
An IP blacklist is a list of IP addresses or domains flagged for sending spam or malicious content.
How can I use this IP Blacklist Checker?
Enter an IP address or domain to check if it is listed in the top 10 major blacklist databases.
Is this tool free?
Yes, this tool is completely free and works for any IP or domain.
Which databases are checked?
Spamhaus, SORBS, Barracuda, SpamCop, Invaluement, UCEPROTECT, DNSBL.info, PSBL, NJABL, RBL.
How do I remove my IP from a blacklist?
First fix the underlying issue such as a compromised device or misconfigured mail server. Then visit the blacklist website and submit a delisting request. Most major blacklists like Spamhaus have a self-service delisting process.
Why is my IP address blacklisted?
Common reasons include a device on your network sending spam, an open relay mail server, or inheriting a blacklisted IP from a previous user. Check your network for malware and review mail server logs.
Can a blacklisted IP affect email delivery?
Yes. If your IP is blacklisted, email servers will reject or filter your messages. This is the most common cause of email delivery failures for businesses running their own mail servers.
How long does it take to delist from a blacklist?
After submitting a delisting request and fixing the underlying issue, most blacklists remove your IP within a few hours to a few days. Spamhaus and Barracuda typically process requests within 24 hours.

What Is an IP Blacklist?

An IP blacklist (also called a blocklist or DNSBL) is a real-time database of IP addresses flagged for sending spam, hosting malware, or performing malicious activity. Email servers, firewalls, and security systems query these lists automatically to block traffic from known bad sources. If your IP appears on a blacklist, your emails may be rejected and your website traffic may be filtered.

How to check if your IP is blacklisted

Enter your IP address in the checker above. The tool queries the most important blacklist databases simultaneously and shows you the result for each. A clean result means your IP is not listed. A flagged result shows which databases have listed your IP so you can start the delisting process.

How to remove your IP from a blacklist

First identify and fix the underlying issue - usually a compromised device sending spam or a misconfigured mail server allowing open relay. Then visit the specific blacklist website and submit a delisting request. Most major blacklists including Spamhaus have a self-service process. After delisting, email delivery typically resumes within a few hours.

Why is my IP blacklisted?

Common reasons include: a device on your network infected with malware and used to send spam, a mail server misconfigured as an open relay, your IP previously assigned to someone who was blacklisted, or your IP caught in a mass blacklisting of a shared hosting range. Check your network for infected devices and review your mail server configuration.

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