Bulk email domain blocklist checker: which addresses are at blocklisted domains?
In short: Paste email addresses and see which sit at a domain listed on URIBL or the NordSpam DBL, with the list that named it and a link to the list's own lookup page in the CSV. Limit: Reads the domain, never the mailbox: a listing says something about the domain, not the person.
A bulk email domain blocklist checker reads the domain after the @ in each address and asks two public blocklists, URIBL and the NordSpam DBL, whether it is listed. Paste up to 50 unique domains per ten minutes, or 250 after a free Google sign-in, and every address gets a row: Listed, Not listed or Unclear. It checks the domain, not the mailbox. Download the CSV.
Price: this tool is free. Checking a whole email list is from $9/mo, and the first 100 checks are free with Google, no card. Check your list free nowSee pricing
Sample result
tom@globex.example is at a domain that URIBL lists.
- Address
- tom@globex.example
- Domain
- globex.example
- Listed on
- URIBL
What this means for you
A listing says something about the domain, not the person. Not listed here doesn't mean not listed anywhere.
- URIBL and NordSpam DBL
- Each list tested before it is trusted
- Link to the list's own lookup
- CSV out, nothing emailed
- Blocklist
- URIBL
- DNS
By SimpleVerifier Team · Last updated
Got a list with addresses at domains that may be flagged for spam?
- Paste it above to find the addresses at blocklisted domains, with a CSV of every row.
- Upload or paste it at /verify. Every address gets a live mailbox check, and the first 100 email checks are free with a Google sign-in, no card.
How do I check whether the domains on an email list are blocklisted?
- Paste email addresses, one per line, or upload a CSV. Addresses are found anywhere in the text, so a whole export works.
- Press Check domain blocklists. Only the unique domains, never the mailbox names, are sent as DNS queries to the lists, 10 a request. Nothing is sent to the domains.
- Read each row: Listed on a blocklist, Not listed or Unclear, with the list that named the domain.
- Filter to the listed addresses, download the CSV, and hand the rest to the mailbox check.
Example
- You enter
- Three addresses:
jane@acme.example(not listed),tom@globex.example(on a blocklist) andana@initech.example(a list gave no answer). - You get
- jane: Not listed. tom: Listed on a blocklist, naming the list and linking its lookup page. ana: Unclear, naming the list that gave no trustworthy answer. Download the CSV.
- Limits
- Up to 50 unique domains per ten minutes without an account and 250 when signed in with Google. 10 domains a request; DNS queries to the blocklists only.
Which blocklists does it query?
Two: URIBL and the NordSpam DBL, both public DNS blocklists in the style RFC 5782 describes. Each is queried together with its own test entry, so a list that refused the query or went silent is reported as Unclear and never read as clean.
Spamhaus DBL and SURBL are not queried, because their free terms exclude commercial sites. For those, use the lists' own lookup pages.
What does a listed domain mean for an address?
These lists name domains that appear in spam messages. Mail from or linking to a listed domain can be filtered, so an address there is a weaker target. A listing says something about the domain, not about the person.
For the mail servers' IP addresses, use the bulk MX blacklist checker. To check domains without the addresses, use the bulk domain blacklist checker.
Why does a clean result prove so little?
Not listed here doesn't mean not listed anywhere: only two lists are asked, and a new domain may not have been listed yet. The check also treats a free provider like gmail.com as one domain, so its result says nothing about a single mailbox.
Use it as a quick screen, then check the rest of the list with the mailbox check.
Who uses this tool, and for what?
- Marketers
- Remove addresses at spam-listed domains before an import.
- Sales teams
- Skip prospects whose domain is on a blocklist that filters your mail.
- Agencies
- Add a blocklist column to a client list audit and export it as CSV.
- Developers
- Screen a signup export for domains known from spam.
What can’t this tool tell you?
- Reads the domain, never the mailbox: a listing says something about the domain, not the person.
- Only URIBL and the NordSpam DBL are queried; not listed here doesn't mean not listed anywhere.
- 50 unique domains per ten minutes without an account, 250 signed in; the limit is counted over ten minutes, not per run.
- A list that refused the query shows as Unclear; run the list again later.
Common questions
- How do I check if the domains on an email list are blocklisted?
- Paste the addresses into a bulk email domain blocklist checker like this one. It reads each address's domain and asks URIBL and the NordSpam DBL about it.
- Is this bulk email domain blocklist checker free?
- Yes. It is a free tool: up to 50 unique domains per ten minutes with no account, and up to 250 when you sign in with Google, with no card.
- Does it tell me whether the mailbox exists?
- No. It checks the domain, not the mailbox. A domain that is not listed can still hold a closed mailbox.
- Why only two blocklists?
- The free terms of Spamhaus DBL and SURBL exclude commercial sites, so they are not queried. Check a domain at their own lookup pages if it matters.
- What does Unclear mean?
- A list refused the query, timed out or failed its own test entry, so there is no trustworthy answer from it. Run the list again later.
- Does it send an email to the domain?
- No. It sends DNS queries to the blocklists only. Nothing is sent to the domains.
Sources
A tidy list can still be full of dead addresses.
Extracting, deduplicating and syntax checks all work on the text of an address. None of them can tell whether the mailbox exists. Only the server that hosts it can answer that, through an SMTP check, and that is what the paid product does.
- Upload the cleaned file as it is: CSVs up to 100,000 rows
- A real SMTP mailbox check on every row, with catch-all detection
- Small list? Starter at $9/mo covers 2,500 emails a month, cancel anytime
Plans from $9 a month, cancel anytime, no contract. Sign in with Google and your first 100 email checks are free, no card. The free tools stay free either way.