How to Check if Your Domain Is on a Blacklist (URIBL, NordSpam and More)

To check whether your domain is on a blacklist, ask the domain blocklists over DNS. Enter the domain in the domain blacklist check for one name, or paste a list into the bulk domain blacklist checker. Both query URIBL and the NordSpam DBL, and report which list holds the domain and why. A list that does not answer is shown as Unclear, never as clean.

A domain can be listed even when every sending IP you use is clean, so this is a different check from an IP lookup. It is also one of the first things to rule out when mail suddenly lands in spam.

IP lists and domain lists are different

IP blocklists list the servers that send spam. Domain blocklists (URIBLs and RHSBLs) list the domains that appear in it. That means the domain in a link in the message body, or the domain in the sender's address. A receiving server can score a message down because of a domain it contains, even if it came from a perfectly clean IP.

Both kinds are published as DNS. You ask for example.com followed by the list's zone name and read the 127.0.0.x answer. RFC 5782 describes the format. Because the listing is about the name, moving to a new sending IP does not clear it. For the IP side, see how to check if an IP address is blacklisted.

Step 1: collect every domain you use

Check more than the domain in your From address. Include your tracking and link domains, any link shortener you use, the domains you send cold email from, and the domains your landing pages sit on. A listing on a tracking domain can hurt a campaign even when the brand domain is fine.

Paste domains, email addresses or URLs, one per line. Up to 50 are accepted without an account, or 250 after a free Google sign-in, counted over ten minutes. Each is reduced to its registered domain, so mail.acme.com is looked up as acme.com and the row shows the name that was queried.

Step 2: run the check and read each row

Each domain is looked up on two lists, and each list is also asked for its own test point. That second query is what stops a silent or refusing list being read as clean.

Result	What it means	What to do
Listed	A list holds the domain. The row gives the list, its reason and a lookup link	Look at what the domain sends and links to, fix it, then follow that list's removal steps
Not listed	Both lists answered and neither holds it	Nothing to fix here. Check authentication and complaint rates next
Unclear	A list timed out, refused the query or failed its test entry	Run the domain again later

URIBL answers with a bitmask, and each bit is a different list: black is its high-confidence list of spam domains, grey covers domains found in bulk mail that may catch legitimate senders, and red is a watch list that includes new domains. The domain blacklist check explains how to treat each; a black listing is a real problem, while red on a brand-new domain often clears as the domain builds history.

Which lists are checked, and which are not

URIBL's public multi list and the NordSpam DBL, because their published terms allow a free tool to query them over DNS at low volume. The terms are on URIBL's about page and NordSpam's usage page.

Spamhaus DBL and SURBL are not queried. Their free terms are for non-commercial use, and we run a commercial service, so the results link to their own lookup pages, which anyone can use by hand: check.spamhaus.org and SURBL's lookup. If you are listed on SURBL, our guide to a SURBL-listed domain covers what to do.

A clean result here is therefore an answer from two lists, not from every list that exists. Answers are also cached for 15 minutes to keep load on the lists low.

Step 3: what to do about a listing

Work out why the domain appeared, fix that, then use the list's own removal process. Domain lists catch domains used in spam, but also domains that only appear in links: a hacked site, a shared link shortener, or a tracking domain that other people also use. Mail with a spike of hard bounces from a stale or bought list is another common route to trouble.

Requesting removal while the cause continues usually produces another listing. The steps are in how to get off a blacklist. Whether a listing hurts your mail also depends on whether the receiving server uses that list, which most do not disclose.

Buying an aged or expired domain

A listing follows a domain from owner to owner. If you are about to buy an aged or expired domain, paste your shortlist into the bulk checker first. It will not tell you the domain's history, but it will catch a current listing before you spend money. Our post on aged and expired domains for cold email covers the other risks.

What this check cannot do

• It checks two public domain lists. Spamhaus DBL, SURBL and the lists mailbox providers keep privately are not included.
• Not listed is a point-in-time answer, and answers are cached for 15 minutes.
• It checks the registered domain, not the exact host.
• It does not check sending IPs. Use the bulk IP blacklist checker for those.
• The limit is 50 domains per ten minutes without an account and 250 signed in.

Keep the domain off the lists

Bounces are the part of a listing you control most directly. Upload the list you send to on the verify page: the first 100 email checks are free with a Google sign-in, no card. Every address comes back valid, risky or invalid with a reason, and you can download only the safe-to-send rows. Nothing is sent to the people on the list. For bigger or recurring lists, see bulk email verification, list cleaning and pricing.

Check your domains now

Use the bulk domain blacklist checker for a list, or the domain blacklist check for one.