IP reputation
Is this IP on a blocklist?
Check any IP address against the major DNS blocklists mail servers actually consult, and see a clear reputation verdict with the reason behind it.
01How it works
The verdict, and the evidence for it.
Live blocklist query
The address is checked against the blocklists receiving mail servers use, in real time, not a stale cached list.
A reason, not a number
Each provider is shown individually, so a listing is always traceable to a specific blocklist rather than a black-box score.
Refusals are not listings
When a provider declines to answer, we say so instead of miscounting it as a listing. The score reflects only real results.
FAQ
About IP reputation
Which blocklists do you check?
The DNS blocklists mail servers actually consult, including Spamhaus ZEN, SpamCop, Barracuda and several others, eight in total.
My IP is listed. What now?
Each blocklist publishes its own delisting process. Start with the provider that lists you; a listing on a major one like Spamhaus is worth resolving before sending at volume.
Is there a limit?
No daily limit and no sign-up. A verification step runs on each check to keep the tool from being automated, and a light background guard protects the underlying providers.
Why does one provider say “not checked”?
Some blocklists rate-limit or refuse queries from shared resolvers. We report that honestly rather than treating a refusal as a clean or a listed result.
Protect your sending reputation.
Verify recipients before you send, with scored and explainable results. Start with 100 free credits, no card.