Check whether the IP your domain sends mail from is listed on DNS blacklists. See which lists answered, which ones listed you, and what to do next.
We read your sending IP from SPF, then query live DNS blacklists for it and for your domain. Nothing to install, no signup to see your result.
Enter your domain and we read the sending IP from its SPF record, then query the same DNS blacklists the full Humerly audit uses:
ip4: mechanism in its SPF recordEach list returns its own answer. The page shows those answers. It does not invent a score or a placement rate.
Mail receivers and filters consult DNS-based block lists (DNSBLs / RBLs) when they decide how to treat mail from an IP or domain. A typical lookup asks: "is this IP in this list?" The list answers with a special A record if it is, or nothing if it is not.
This checker:
ip4: mechanismWhy SPF and not your MX. A blacklist lists addresses that send mail. Your MX names the host that receives it, and for most domains that is a third party — if your MX points at Google or Microsoft, checking it grades their reputation and prints it as yours. Your SPF ip4: entry is your own published statement of which addresses send your mail, which is exactly the set a sending blacklist is about.
If the resolver that backs these lookups is unhealthy, the engine returns CHECK_UNAVAILABLE rather than a false clean. If your domain does not tell us which IP it sends from, the engine says so instead of reporting a clean sweep it never ran. That honesty rule matters: a failed check, and an unrun one, must never look like a pass.
Clean. No list in this run returned a listing for your sending IP or domain. That is good news for this snapshot. Lists change. Re-check after infrastructure changes, and keep authentication (SPF, DKIM, DMARC) healthy so you do not earn a listing later.
Listed. One or more lists returned a hit. The page names each list from the engine response. Delisting is done with that list's own process. Fix the underlying cause first (compromised host, open relay, spam complaint pattern, bad neighbor IP), then request removal.
Unavailable. The check could not complete for some or all lists (resolver health, control-code answers, or rate limits). This is not a clean result. Try again shortly. Do not treat silence as a pass.
Sending IP undetermined. Your domain does not publish an ip4: address in SPF, so there is no address of yours to look up. This happens when you have no SPF record, or when SPF delegates sending entirely to a provider with include: or redirect=. It is not a clean result and it is not a failure — it means the IP lists were not checked. Domain-based lists are still reported, because those key off your domain rather than an address. To get an IP verdict, publish the address you send from as ip4: in SPF.
No MX / domain not resolvable. Without a usable mail host and public IP, this check cannot run. Fix DNS first, then re-check.
Compromised or abused host. Malware or a hijacked account sends spam from your IP. Clean the host, rotate credentials, then delist.
Open relay or misconfigured MTA. Fix the mail server so it only accepts mail you intend to send.
Shared IP neighbor. On shared hosting, another tenant's traffic can land the IP on a list. Move to a dedicated IP if the provider cannot clear it.
Authentication gaps. Missing or broken SPF, DKIM, or DMARC does not by itself equal a listing, but it makes abuse and spoofing easier. Run the full audit and close those gaps.
False positives and stale listings. Some lists are aggressive. Use the list name the engine returned, read that list's delist policy, and appeal with evidence.
This tool reports DNS blacklist answers for your sending IP and domain. It does not measure where your emails land, because placement depends on how your domain behaves over time, not on a single list lookup. Any tool that promises an inbox rate from a blacklist check is guessing.
It checks the first ip4: address in your SPF record. If you send from several addresses, the others are not looked up in this run.
A clean blacklist snapshot is one signal. Authentication, sending behavior, and list membership over time are the rest of the picture.
The full Humerly email setup audit checks MX, SPF, DKIM, DMARC, TLS-RPT, MTA-STS, BIMI, and blacklist status, then hands you a single Email Setup Score with a numbered fix plan.
Run the full setup auditWhat is a DNS blacklist?
A DNS-based list that marks IP addresses or domains associated with abuse. Receiving systems query these lists when deciding how to treat mail.
Does a listing mean all my mail is blocked?
Not always. Impact depends on which list, which receivers consult it, and whether you are still sending from that IP. Treat any listing as urgent to investigate.
Which IP do you check?
The IPv4 address your domain sends from, read from the ip4: mechanism in its SPF record. Not your MX — the MX receives mail, and on most domains it belongs to a mail provider, so checking it would report that provider's reputation instead of yours. If your SPF publishes no ip4: address, we say the sending IP is undetermined rather than report a clean sweep we did not run.
Why might a check say unavailable?
The resolver behind the lookups may be unhealthy, a list may return a control code instead of a real answer, or you may be rate-limited. The engine refuses to call that clean.
How do I get delisted?
Use the list name shown in the result, follow that list's removal process, and fix the cause first so you are not re-listed immediately.
Is a clean result permanent?
No. It is a point-in-time answer. Re-check after changes, and monitor if you send at volume.