Monitor your IP blocks against 25 live DNS blocklists. Get alerted the moment a listing appears — before it impacts your email delivery, hosting customers, or infrastructure.
We built RepRadar from the ground up on dedicated infrastructure — not a shared API wrapper. That means real speed, real accuracy, and features competitors can't match.
Priced by block size — not by number of monitors. You own a /22, you pay for a /22. No counting monitors, no confusing tiers.
All plans include a 5-day free trial. No credit card required to start.
Fewer lists than some tools advertise, and that is the point. A blocklist that has shut down often answers every query with a listing — quoting a bigger number by including dead zones manufactures false positives against your own addresses.
The things people ask before pointing RepRadar at their space.
A DNS blocklist is a published list of IP addresses associated with spam, malware or abuse. Mail servers and some networks query these lists in real time and reject traffic from anything listed. A listing you do not know about shows up as mail that silently stops being delivered.
Those check one address, once, when you remember to. RepRadar checks every address in a block on a schedule and tells you when something changes. The listing that causes an outage is almost always the one that appeared after you last looked.
Because 25 is how many are actually alive and worth querying. Several widely-quoted lists — SORBS, NiXSPAM, LashBack — have shut down, and a decommissioned zone can answer every query with a listing. Quoting a bigger number by including dead zones manufactures false positives against your own addresses.
Anything from a single address up to a /19 on the top plan, and larger by arrangement. Pricing follows block size and how often you want it checked, because both determine how many queries it takes.
At your check frequency — daily on the entry plan, down to hourly on the top one. The alert goes out on the check that first sees the listing, by email to up to two addresses and to a webhook if you have set one.
Yes. Set a webhook URL in your alert contacts and we POST a JSON payload to it that both Slack and Discord render directly. Any endpoint that accepts a POST works.
They list entire netblocks and autonomous systems rather than individual addresses, so a perfectly clean address appears listed because an unrelated neighbour misbehaved. We report them for context but never count them toward a clean-or-listed verdict.
No. RepRadar works on any address space you control. If you do lease through IPv4 Hub, monitoring of that block is included for the life of the lease at no extra cost.
Monitoring stops and nothing is charged. Your monitors and their history are kept, so picking a plan later resumes where you left off.
5-day free trial. No credit card required. Setup takes under 2 minutes.