Free email blacklist checker.
Check a sending domain or IP against the public DNS blacklists that answer queries from a browser. A listing here is a symptom rather than a cause, so the page below covers what puts senders on these lists and how delisting actually works.
Privacy: this tool runs entirely in your browser. When you click Check, one DNS query for the domain you typed goes to Cloudflare's public DNS resolver (Google's as fallback). Nothing is stored, logged or sent to GrowthPal.
Blacklists at a glance
| Item | Value |
|---|---|
| What is checked | Public DNS blacklists that answer lookups through public resolvers |
| What cannot be checked here | Spamhaus, which blocks queries arriving via public resolvers, so no browser tool can reach it |
| What a listing means | That list is advising receivers to distrust the address. Effect ranges from a scoring nudge to an outright block |
| The bigger signal | Google and Microsoft lean mostly on internal reputation that no public list exposes |
| Delisting | Each list runs its own process. Some expire automatically, some need a form |
What is a DNS blacklist?
A DNS blacklist, or DNSBL, is a database of IP addresses and domains published over DNS so that receiving mail servers can query it in real time. A receiver takes the connecting IP, reverses it, appends the list's zone, and looks it up. An answer means listed.
Because the whole thing runs over ordinary DNS, the check costs a receiver almost nothing, which is why it happens on essentially every message. Lists differ enormously in what they record and how much weight receivers give them. Some collect spam trap hits, some collect user complaints, some track malware infrastructure, and a listing on one is not equivalent to a listing on another.
For cold email the important thing to understand is that these lists are the blunt end of filtering. Clearing them is necessary and nowhere near sufficient.
How to read your blacklist check result
The checker queries each list in turn and returns one row per list.
Clean means that specific list holds no record for the address you entered. It is not a statement about your reputation generally, only about that one list.
Listed means that list is currently telling receivers to distrust the address. Treat it as urgent, but diagnose before you act: a listing is the symptom of something you did a few days ago, and delisting without fixing the cause buys days rather than weeks.
Could not check means the query failed or the list did not answer. Public resolvers are rate limited, and some lists deliberately refuse queries that arrive through them. Retry before reading anything into it.
The honest limit, which the tool states in its own results: the list that matters most is not in here. Spamhaus blocks lookups through public resolvers like Cloudflare and Google, which is all a page running in your browser can use. Checking it takes a query from a server, so use their own lookup page directly.
A clean sweep here means you have not done anything egregious. It does not mean you are welcome at Gmail.
What each result means
| Result | What it means | What to do |
|---|---|---|
| Clean | No record on that list for this address. | Nothing, but re-check after any volume change. |
| Listed | The list is advising receivers against this address. | Find the cause first, then use that list's delisting process. |
| Could not check | The lookup failed, was rate limited, or the list refused a public resolver. | Retry. Persistent failures mean that list needs a server-side query. |
What actually gets a sender listed
| Cause | How it happens | Prevention |
|---|---|---|
| Spam trap hit | Mailing an address that exists only to catch senders who did not verify. Recycled traps are old real addresses; pristine traps were never real. | Never buy lists. Verify everything before sending. |
| Bounce spike | A stale or scraped segment produces a burst of hard bounces, which reads as guesswork. | Keep bounces under 2%, verified before send. |
| Volume spike | Sending far past what the warmup schedule supported, from a domain with no history. | Follow the ramp. A new mailbox sending fifty a day is not a pattern real mailboxes make. |
| Complaint rate | Recipients marking mail as spam, usually because the targeting was wrong rather than the copy. | Tighter targeting and a plain, obvious way to opt out. |
| Shared IP neighbours | On shared sending infrastructure, somebody else's behavior lists the IP you happen to share. | Dedicated sending infrastructure, separate from your primary domain. |
| Compromised account | Stolen credentials used to send spam through your own infrastructure. | Two-factor everywhere, rotate credentials, alert on volume anomalies. |
How to get delisted, in the order that works
Delisting is the last step, not the first. Every list will re-add an address that is still doing whatever got it listed, and some treat repeat requests as a reason to list for longer.
- Stop sending from the listed address. Pause the campaigns on that domain or IP before anything else. Continuing to send while listed deepens the problem.
- Find the cause in the last seven days. Look at bounce rate by segment, volume against your warmup schedule, and where the newest part of the list came from. The cause is almost always one of those three.
- Fix it at the source. Re-verify the offending segment, drop the part you cannot verify, and reset volume back to the last level that ran clean.
- Use that list's own delisting process. Each one runs its own. Some expire automatically once reports stop, others need a request form, and the form usually asks what you changed. Step 3 is the answer to that question.
- Re-check and allow for DNS caching. A delisting is not visible to every receiver immediately.
- Watch for thirty days. A second listing on the same address tells you step 2 found the wrong cause.
Common questions about blacklists
Why is Spamhaus not in the results?
Spamhaus blocks lookups arriving through public resolvers like Cloudflare and Google, which is all a browser-based tool can use. Checking it requires a query from a server, so use Spamhaus's own lookup page directly. The lists here are the ones that answer over public DNS.
I am listed. How do I get off?
Find the cause before you file anything: a bounce spike from an unverified list, volume that ran ahead of warmup, or a spam trap that should never have been on the list. Fix that, then use the list's own delisting form. Delisting without fixing the cause buys days, not weeks.
Should I check the domain or the IP?
Both, because they mean different things. An IP listing hits whatever is sending, which on shared sending infrastructure can be someone else's doing. A domain listing is yours alone and is the more serious signal for cold email.
Every list says clean but I still land in spam.
That is normal. Public blacklists are the blunt end of filtering. Google and Microsoft lean mostly on internal reputation that no public list exposes. Clean here means you have not done anything egregious, not that you are welcome.
How long does delisting take?
It depends entirely on the list. Some expire on their own within a day or so once the reports stop, others hold until you submit a request and then process it in their own time. DNS caching adds a further delay before every receiver sees the change, so allow for both.
Does a single listing really hurt deliverability?
It depends which list and which receiver. A listing on a minor list is a small negative signal that a large provider may ignore entirely. A listing on a major one can move your mail to spam at scale. Either way it is a sign something upstream went wrong, which is the part worth acting on.
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