Blacklist (RBL) Checker
Check an IP or domain against the major email blacklists at once.
About the Blacklist (RBL) Checker
Query more than twenty widely used DNS blacklists — Spamhaus, SpamCop, Barracuda, SORBS, UCEPROTECT, SpamRats and others — for a mail server IP or a domain. Listings show the return code and the reason text the list publishes, so you know exactly why delivery is failing and where to request removal.
Examples
Check an IP
203.0.113.10Output
Clean on 20 lists, listed on 1Keyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Version 1.0.0 · Updated 2026-09-16 · Runs entirely in your browser