Email blacklist check
Enter a domain to look it and its mail servers up on public DNS blocklists. A list that does not answer is shown as such, never as clean.
How to read the result
Each row is one list and one thing looked up on it. Listed: the list names it, with its reason where the list gives one. Not listed: the list answered and does not name it. No answer: the list timed out or refused the query; that says nothing either way. Not checked: the list needs a key this server does not have.
Most delivery problems are not blocklists but missing authentication. If nothing is listed and mail still lands in spam, check SPF and DMARC, or everything at once with the domain health check.
Questions
- Which blocklists are checked?
- SpamCop, PSBL, Mailspike, Spamhaus ZEN, Spamhaus DBL. Spamhaus is queried only through its Data Query Service; when this server has no key for it, the result says "not checked" rather than "not listed", and you can look it up at check.spamhaus.org.
- What is checked: my domain or my IP?
- Both where a list supports it: domain lists get the domain, IP lists get the addresses of the domain's mail servers from its MX records. If you send through Resend, SES or Postmark, your mail leaves from their servers, which they monitor themselves.
- My server is listed. What now?
- Find out why before asking for removal: an open relay, a hacked account or form, or mail to a bought list. Each list's page, linked in the result, explains its reason and how to request removal. Fixed causes usually clear within a day or two; unfixed ones come back.
- What does PBL mean?
- Spamhaus PBL lists end-user IP ranges, such as home connections, that should not send mail directly. It is a policy listing, not a spam report. A mail server in such a range should send through a relay.
More free tools
No sign-up, nothing stored. All tools.
Domain email health check
SPF, DMARC, MX and blocklists for a domain in one report, with what to fix first.
SPF record checker
Parses the SPF record, counts its DNS lookups against the limit of 10 and says how to fix what breaks it.
DMARC checker
Reads the DMARC policy, report addresses and alignment, and says what the policy actually does to spoofed mail.
DKIM checker
Reads a DKIM key by selector, or searches the common ones, and checks its type and length.
MX lookup
The mail servers of a domain, their addresses and who hosts the mailboxes.
Email provider lookup
Which mailbox provider and which sending services a domain uses.
Email address verifier
Format, mail servers, throwaway domains, role addresses and typos for one address.
Bulk email checker
Up to 100 addresses from a pasted list or a CSV, with a CSV of the results. Nothing stored.
Disposable email checker
Whether an address or domain belongs to a throwaway-mail service.
Email HTML preview
Paste email HTML, see it on desktop and phone with images on or off, and what breaks in Gmail and Outlook.
Merge tag tester
A template with {{tags}} and JSON data in, the email out, with every tag that would reach the recipient unfilled.
Subject line checker
How a subject and preheader look in iPhone Mail and Gmail, where phones cut them, and what reads like a pitch.