New Playbook: Cold Email Infrastructure Setup Guide

Read Now arrow_forward
Mailsfinder Mailsfinder
Mailsfinder Mailsfinder
Pricing
Compare
Contact
Log In Start Free Trial
Free Tool, No Signup

Free email blacklist checker: see if a domain or its mail server is on a spam blocklist

Paste an email address or a domain. We look up its mail servers and test each one against five public DNS blocklists (SpamCop, Barracuda, PSBL, UCEPROTECT, s5h). If a receiver would refuse mail from that server, you see which list caused it. No signup. 5 free checks a day.

Try it

security Enter an email or domain above to check the blocklists.

What an email blacklist check does

A blacklist, or DNS blocklist, is a public database of mail-server IP addresses that have been caught sending spam or hitting spam traps. Receiving mail servers query these lists on every incoming connection. If your sending server is on one, your message is filtered or rejected before anyone reads it, and you usually find out from a bounce message weeks later.

This checker does the same lookup a receiving server does. It resolves the MX records for the domain you enter, turns each mail server into an IP address, reverses that IP and queries five blocklists. A listing means that specific IP was reported. A clean result means none of the five lists know it, which is good news but not a guarantee: Spamhaus and a few enterprise filters keep private data that public queries cannot see.

Checking the sender side of an address is the mirror image of verifying it. Verification asks whether the recipient exists. A blacklist check asks whether the recipient will even accept mail from you.

What this checker looks at

dns

MX records

Finds the mail servers for the domain, in priority order, and tests up to three of them.

lan

Server IP addresses

Each mail server is resolved to its IPv4 address. Shared hosting means one IP can serve many domains, so a listing may come from a neighbour.

shield

Five public blocklists

SpamCop, Barracuda, PSBL, UCEPROTECT Level 1 and s5h. Each answers from a different source: user reports, spam traps, or observed sending behaviour.

fact_check

Real listing codes only

Blocklists answer error codes when they refuse a query. Those are not listings, and this tool does not count them. Spamhaus and URIBL refuse shared-host lookups and are left out for that reason.

Why a listing matters

5

Public blocklists queried on every check, each with its own delisting process.

6 hrs

Results are cached, so you can re-check a domain after requesting delisting without waiting.

< 2%

Bounce rate the big inbox providers tolerate before they start throttling you.

Pricing

Free

$0

100 verified lookups per day, forever. No card.

Monthly

$9.99/mo

300,000 credits per cycle.

Lifetime

$249 once

2,000,000 credits, lifetime pool.

Frequently asked questions

My domain is listed. What do I do? expand_more
Open the listed blocklist's website (each has a lookup page), search your IP, and follow its delisting request. SpamCop delists automatically after 24 hours without new reports. Barracuda and UCEPROTECT have request forms. Before you ask, fix the cause: a compromised account, an open relay, or a list full of spam traps, or you will be re-listed within days.
The listed IP is not mine. Why does it show for my domain? expand_more
Your MX record points at a mail provider. If you use Google Workspace, Microsoft 365 or a shared host, the IP belongs to them and serves thousands of domains. A listing there is their problem to fix and rarely affects delivery, because large providers are whitelisted by most receivers.
Why is Spamhaus not included? expand_more
Spamhaus blocks queries from public and shared DNS resolvers and returns an error code instead of an answer. Showing that as a listing would be wrong. Query Spamhaus directly on their site, or from a dedicated resolver, for the authoritative answer.
Does a clean result mean my email will land in the inbox? expand_more
No. Blocklists are one input among many. Authentication (SPF, DKIM, DMARC), the bounce rate of your recent sends, complaint rate and content all count. A clean sending server plus a verified list is the combination that keeps you out of the spam folder.
How is this different from an email verifier? expand_more
A verifier checks the recipient: does the mailbox exist and will it accept mail. A blacklist check looks at the sender: will receiving servers accept mail from this domain's servers. Use both. Verify the list you send to, and check your own domain before a campaign.

Related reading

Tool

Free email verifier

Check whether a specific mailbox exists and accepts mail, with catch-all and disposable flags.

 Tool

Email deliverability checker

SPF, DKIM, DMARC and MX in one report for your sending domain.

 Guide

How to clean an email list

Remove the bounces, traps and role addresses that get senders listed in the first place.

 Listicle

Email deliverability tools compared

Warm-up, monitoring and verification tools tested side by side.

Stop bounces before they get you listed

Verify every address before it goes into a campaign. 100 free checks a day, no card, bulk CSV when you need it.

Get 100 free credits/day Talk to Sales