Look up any IP or domain and get an answer immediately.
An on-demand lookup for one IP or domain at a time: type in the address and get back its listing status across every major blocklist, plus a 0-100 health score. It's built for one-off verification rather than ongoing background monitoring.
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A direct lookup with an answer right away.
No need to add the IP or domain to Sendbox first, run the lookup on anything you're evaluating, vetting, or troubleshooting.
Queries fire concurrently across every major list, returning results in seconds instead of the minutes a sequential check would take.
See precisely which lists flagged the asset, so the right delisting workflow is obvious.
No per-query fees, no monthly cap, and no API plan to negotiate.
Sometimes you just need the answer on one specific IP, immediately.
Paste any IPv4 address or domain into the lookup box, it doesn't need to be connected to your Sendbox account first.
The query fans out across every major email blocklist at once, so results come back in seconds instead of the minutes a sequential check would take.
A single 0-100 health score gives you a quick read, and a per-blocklist breakdown is there if you need to know exactly which list flagged the asset and what delisting process applies.
A domain you inherit also inherits any listings that came with it. Run the lookup before buying to avoid paying for a domain that already needs delisting work.
If one campaign's open rates suddenly crater, the lookup can tell you within seconds whether a fresh listing on the sending IP is to blame.
After filing a delisting request, run the lookup a few hours later to confirm it actually went through before you resume sending.
A lookup tool, distinct from a monitoring service.
A free standalone lookup instead of a metered API plan
Most blacklist lookup services charge per query or gate access behind an API plan. Sendbox's in-dashboard lookup is free and unmetered for its customers, which means it stops feeling like something to ration and becomes a tool you actually reach for.
When to reach for the lookup vs the monitoring service
The lookup exists for verifying one specific asset on demand, a domain you're about to buy, an IP a colleague flagged, a sending address you suspect is causing a problem. Continuous monitoring handles the ongoing surveillance for assets already sitting in your account. They're different tools solving different jobs, and most teams end up reaching for both at different moments.
Per-blocklist visibility, not just a score
The 0-100 score gives you the fast answer, while the per-blocklist breakdown gives you the actionable one. Which specific list flagged the asset determines which delisting workflow applies, since every major blocklist runs its own removal process, and the lookup surfaces that detail instead of hiding it behind a single number.
Got questions? We've got answers.
Still stuck? Talk to us →No. The lookup accepts any IP address or domain, including ones that aren't part of your Sendbox account at all, which is exactly what makes it useful for vetting a domain before you buy it or checking an asset you don't even own.
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