Free Blacklist Checker
Check if your domain or IP address is on email blacklists. Identify deliverability issues before they impact your campaigns.
Want to check your email authentication? Use our Email Domain Checker
What is an email blacklist?
Email blacklists (also called DNSBLs or blocklists) are databases that track IP addresses and domains known to send spam. When you send an email, the receiving server may check these lists to decide whether to deliver your message, send it to spam, or block it entirely.
Think of blacklists as a reputation system for email senders. If your sending IP or domain appears on a blacklist, it signals to email providers that you may not be a trustworthy sender, which can severely impact your email deliverability.
Why blacklist monitoring matters
Protect your deliverability
Being blacklisted can cause your emails to bounce or land in spam folders. Regular monitoring helps you catch issues early, before they impact your campaigns or customer communication.
Maintain sender reputation
Your sender reputation is built over time and can be damaged quickly. Blacklist listings contribute to poor reputation scores, which persist even after you get delisted.
Identify security issues
Sometimes blacklisting indicates a compromised server or account sending spam without your knowledge. Discovering a listing can alert you to security problems that need immediate attention.
Diagnose delivery problems
If your emails suddenly stop reaching recipients, blacklisting is one of the first things to check. This tool helps you quickly rule out or identify blacklisting as the cause.
Common reasons for blacklisting
- Spam complaints: Too many recipients marking your emails as spam
- Spam traps: Sending to old, recycled, or honeypot email addresses designed to catch spammers
- High bounce rates: Sending to many invalid addresses suggests poor list quality
- Compromised server: Hackers using your server to send spam without your knowledge
- Shared IP issues: Another sender on your shared IP triggered the listing
- Sudden volume spikes: Rapidly increasing send volume can trigger spam filters
How to get removed from a blacklist
- Identify the cause: Before requesting removal, understand why you were listed. Check for compromised accounts, review your email practices, and clean your list.
- Fix the underlying issue: Remove spam traps and invalid addresses, improve your opt-in process, secure any compromised systems, and ensure you have proper authentication (SPF, DKIM, DMARC).
- Request delisting: Visit the blacklist's website and follow their removal process. Most have a self-service form. Be patient and honest about the steps you have taken.
- Monitor and prevent: After removal, monitor regularly to catch any recurrence. Implement better email hygiene practices to prevent future listings.
Blacklists and email authentication
Proper email authentication (SPF, DKIM, DMARC) will not directly remove you from blacklists, but it helps prevent future listings by proving your emails are legitimate. It also makes it harder for spammers to forge emails from your domain, which could otherwise damage your reputation.
Use our SPF Generator, DKIM Generator, and DMARC Generator to set up proper authentication for your domain.
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SendScale monitors your sender reputation, warms up new domains, and helps ensure your emails actually reach the inbox.
Try SendScale FreeFrequently Asked Questions
An email blacklist (also called a DNSBL or blocklist) is a database of IP addresses and domains that have been flagged for sending spam or malicious emails. Email providers use these lists to filter incoming mail. If your IP or domain is on a blacklist, your emails may be blocked or sent to spam.