IPv4 Blacklist Checker

What is a RBL?

A Real-Time Blackhole List (RBL), also known as a blocklist or Domain Name System-based Blacklist (DNSBL), is a list of IP addresses, domain names, or Universal Resource Locators (URLs) that are known to be sources of spam or security threats. RBLs are used by internet mail servers to check the origin of incoming emails in real-time and determine if they are legitimate. This can help to reduce the load on a mailbox’s spam filters.

How can I get my IP off an RBL list?

Each RBL website will have instructions on how to request delisting. It’s important to solve the underlying email problem before you request your IP be unblocked. This can involve changing passwords, Adding a Sender Policy Framework (SPF) Record and Enabling DomainKeys Identified Mail (DKIM), reconfiguring your email forwarding, or speaking to email users on your server. If you request delisting but your server still appears to be sending spam, your IP will be relisted and it will be more difficult to delist a second time.

What problems will blacklisted IPs cause?

If your IP address is listed on an RBL, you might have trouble sending legitimate email and will get error messages. If you see that your email is being rejected, it’s easy to check if your server’s IP is listed on any RBLs by using an online RBL checker. Remember that RBL usage is set by the receiver, not the email sender. This means you don’t have control over the RBLs your email recipients are using to filter their email. People can usually request to have their IPs delisted from RBLs, and some lists delist IPs automatically after a period of time.

Firstly, don’t panic. Each RBL website will have instructions on how to request delisting. It’s important to solve the underlying email problem before you request your IP be unblocked. This can involve changing passwords, Adding a Sender Policy Framework (SPF) Record and Enabling DomainKeys Identified Mail (DKIM), reconfiguring your email forwarding, or speaking to email users on your server. If you request delisting but your server still appears to be sending spam, your IP will be relisted and it will be more difficult to delist a second time.

How can I prevent my IP/domain from being blacklisted?

Ensure your email marketing practices comply with anti-spam laws, keep your mailing lists clean and up-to-date, secure your mail servers against unauthorized use, and regularly monitor for any unusual activity. Our service also offers advice and best practices to help keep you off blacklists.