RBL Record Lookup

Enter a domain name or IP to perform RBL check.

This RBL (Real-Time Blacklist) Lookup tool allows users to check whether an IP address is listed in 60+ RBLs. You can either input a DNS name (e.g., example.com) or an IP address (e.g., 192.168.1.1). If a DNS name is entered, the tool automatically resolves it to its corresponding IP address. Once the "Submit" button is clicked, the tool queries various RBLs to obtain reputation data for the IP address.

The results are presented in a table with the following details:

• RBL: The name of the blacklist.
• Status: The result for each RBL, which will either be "Listed" (IP is found in the RBL), "Not Listed" (IP is not found), or "Error" (the lookup failed due to connectivity or DNS server issues).
• Info: The status code for the listed IP, typically an address from the loopback range (127.0.0.0/8). When available, additional data about why the IP address was blacklisted is provided.

Note that status code values and their meanings vary significantly between RBLs. Many blacklists may use different values to provide reason for why an IP address is blacklisted. For example, to categorize the type of malicious activity associated with the IP, such as phishing, spam, or malware distribution. It is recommended to visit the RBL's web site to obtain the detailed status code descriptions.

For domain-based lookup use our URL BlackList Checker.

A Real-Time Blacklist (RBL), also known as DNSBL, is a database of IP addresses that are flagged for sending spam, malware, or other types of unsolicited content. These blacklists are maintained by organizations that collect and analyze data about malicious or suspicious activity across the internet. RBLs can be utilized by email servers and other security systems to filter out emails or connections from potentially harmful sources.

When a server receives an email or a connection request, it can perform a lookup against RBLs to determine if the sender's IP address is listed. If the IP is found in the blacklist, the email may be blocked, marked as spam, or quarantined depending on the server's configuration.

Using RBLs is essential for email security and spam control. They allow businesses and service providers to block unwanted messages from known spammers, preventing them from reaching users' inboxes. Additionally, RBLs help protect servers from receiving malicious traffic, such as phishing or malware-laden emails.

Checking whether your email server's IP is listed on various RBLs can help diagnose deliverability issues. For instance, if the IP address is blacklisted, legitimate emails may get marked as spam or outright rejected. Understanding which RBLs list your IP and why can be a crucial step in resolving these issues, improving email deliverability, and maintaining a good reputation in the email ecosystem.

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