Type your domain. We ask public blocklists (also called blacklists) like Spamhaus, Barracuda and SpamCop about your domain and the IP it points to, and show you every answer.
Asking each list. This usually takes 5 to 10 seconds.
These lists have an entry for your domain or its IP. Confirm each one on the list's own lookup page before you act.
Look the listing up on the list's own site first. Most lists remove an entry once the cause is fixed. Our team can look at it with you.
Leave your email and we'll write back.
Why it matters
A blocklist (also called a blacklist, or DNSBL) is a public list of IP addresses and domains that have sent spam. Mail servers check these lists before they accept your email. If you are on one, your email can be refused or filed as spam, and nobody tells you or the person you wrote to.
High bounce rates, spam complaints, sending without SPF, DKIM and DMARC, or an IP that someone else used for spam before you. Honest senders get listed too.
A listing on a big list like Spamhaus or Barracuda can keep much of your email out of the inbox. Many servers drop it quietly, without a bounce to tell you.
Fix the cause first: stop the complaints, clean your list, set up SPF, DKIM and DMARC. Then use the removal form on the list's own site and explain what you changed.
Use double opt-in, remove addresses that bounce, watch your complaint rate, and warm new IPs slowly. Our team does this for the people we send for: we check bounces, complaints and blocklists after every send.
Lists answer differently depending on who asks. Some refuse lookups from shared DNS resolvers, and some reply with an error code instead of an answer. If a result surprises you, check it on the list's own lookup page.
We check the IP your domain's website points to. Your email may be sent from a different server, so a clean result here does not cover every address you send from.
We warm new domains and IPs slowly. After every send we check bounces, complaints and blocklists, and fix what breaks.