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DNS & Infrastructure
Blacklist Checker
Check any IP or domain against 40+ blacklists including Spamhaus, Barracuda, SORBS, SpamCop, and UCEPROTECT.
This tool is being wired up. The analyzer ships in the next build phase.
About this check
Check IPs and domains against 40+ RBLs in one click.
Frequently asked questions
- What does the Blacklist Checker actually check?
- Check IPs and domains against 40+ RBLs in one click.
- Is this really free?
- Yes. Every on.bo tool is free, no signup required, no rate-limit tricks.
- Do you store the data I check?
- We log minimal metadata to keep the service healthy. Lookups themselves are not retained beyond short-term caching.