Free Email & IP Blacklist Checker
Check if your email, IP, or domain is on any blacklist. Scans 50+ databases and shows your health score instantly.
PressEnter ↵to scan
Your health score will appear here
Enter an email, IP address, or domain. We auto-detect the type and check it against every major DNSBL and URI blacklist.
How it works
3 quick steps from input to answer. No account, no install.
Back to the tool- 01
Enter your email, IP, or domain
We auto-detect the input type and run the right checks.
- 02
We scan 50+ blacklist databases
Real-time queries against every major DNSBL, RBL, and URI blacklist.
- 03
Get your health score and listings
See exactly which lists flagged you, with a 0-100 health score.
Why this matters
Being on an email blacklist means your emails go straight to spam. ISPs and email providers check blacklists before delivering your messages. Even one listing can tank your deliverability. Regular monitoring catches problems before they affect your campaigns.
SendboxStop checking manually
Sendbox monitors all your domains and IPs around the clock. Get alerted the moment you hit a blacklist, not days later.
Automatic monitoring
Get alerted the moment you land on a blacklist
Historical tracking
See your reputation trend over time across all lists
Scheduled checks
Daily automated checks across all your domains and IPs
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An email blacklist (also called a blocklist or DNSBL) is a database of IP addresses and domains that have been flagged for sending spam or malicious content. Email providers check these lists to filter incoming mail.
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