Blacklist Lookup
Enter a URL
Blacklist Checker — Check IP & Email Blacklist Status
Enter an IP address or email domain to check whether it appears on any major spam or security blacklists (RBLs) — the lists email servers and spam filters consult before deciding whether to accept or reject your mail.
Why this matters
If your IP or sending domain lands on a blacklist — even unintentionally, through a shared hosting neighbor's bad behavior or a compromised account — your emails can start silently landing in spam folders or getting rejected outright, with no obvious warning that it's happening. Checking periodically, especially after noticing a drop in email open rates, catches this before it does lasting damage to deliverability.
What it checks
- IP blacklist status — whether your server's sending IP appears on any of the major DNS-based blacklists used by mail providers
- Domain/email blacklist status — whether your sending domain itself is flagged, separate from the IP
Common reasons an IP or domain gets blacklisted
- A compromised server or account sending spam without the owner's knowledge
- Sharing an IP with other sites on cheap hosting, where another tenant's bad behavior gets your IP flagged too
- Misconfigured email authentication (missing or incorrect SPF, DKIM, or DMARC records), which makes legitimate mail look suspicious to filters
- A sudden spike in sending volume that trips automated spam detection
If you find yourself listed
- Identify and fix the underlying cause (clean a compromised account, fix authentication records, or move off a shared IP with a bad reputation)
- Most blacklists have a delisting request process on their own site once the issue is resolved
- Check again here after a few days to confirm removal, since delisting isn't always instant
How it works
- Enter the IP address or domain/email you want to check
- Review which blacklists, if any, flag it
- For a broader domain reputation check beyond just blacklists, pair this with our Suspicious Domain Checker
