How to Use IP Blacklist Checker
1. Enter an IP Address, Subnet, or Range
On the home page, you'll find an input field where you can enter:
- Single IP address - Example:
8.8.8.8 - Subnet in CIDR notation - Example:
192.168.1.0/24(checks all IPs in that subnet, up to 256 addresses) - IP range - Example:
8.8.8.8-8.8.8.20(checks all IPs from the first to the last specified)
💡 Pro Tip: Make sure to enter IP addresses in the correct format. The tool only accepts IPv4 addresses currently.
2. Click "Check"
After entering your IP(s), click the "Check" button. Our tool will then query multiple blacklist databases simultaneously to check if the IP(s) are listed.
This process typically takes just a few seconds, but may take longer if you're checking a large subnet or range. While checking, you'll see a loading indicator.
⚠️ Note: For performance reasons, we limit subnet and range checks to a maximum of 256 IPs at a time.
3. Review Results
The results will show whether each IP is listed or not on the following major blacklists:
- Spamhaus ZEN - A widely-used blacklist for spam sources
- Barracuda - Used by Barracuda email security products
- SpamCop - Based on spam reports from users
- UCEPROTECT - Tracks sources of unsolicited bulk email
For each blacklist, you'll see one of two indicators:
- Clean - The IP is not listed on this blacklist
- Listed - The IP is blacklisted
4. Understand the Summary
For subnet and range checks, you'll also see a summary at the top of the results showing:
- Total number of IPs checked
- Number of IPs listed on at least one blacklist
- Breakdown of listings by blacklist
This summary helps you quickly understand the overall reputation of your IP range.
5. Share Your Results
After checking, you'll receive a unique link that you can share with colleagues or clients. This link provides access to your results for 48 hours without needing to run the check again.
Simply click the "Copy" button next to the link to copy it to your clipboard.
6. What to Do if Your IP is Blacklisted
If you find your IP is blacklisted:
- Identify and fix the issue that caused the listing (secure compromised servers, stop spam, etc.)
- Visit the blacklist provider's website to learn about their specific delisting process
- Follow their delisting procedure, which typically involves submitting a removal request
- After the delisting period (which varies by provider), check again to confirm removal
💡 Pro Tip: Keep in mind that delisting can take anywhere from a few hours to several days depending on the blacklist provider.