Blacklist Look Up

The blacklist look up tool looks up whether a domain's mail server IP address (or a specific IP you provide) is listed on major DNS-based blacklists (DNSBLs) used to filter spam.

Domain name

What do you want to look up?

Blacklist Look Up

Looks up whether this domain's IP address (or the IP address you entered) appears on common email blacklists (DNSBL) — being listed can cause outgoing mail to be rejected or sent to spam.

Also look up blacklist status when I run this search

How to use this tool

Pick a lookup type from the dropdown, or type a shortcut straight into the field — e.g. mx:example.com, all:example.com, spf:example.com, whois:example.com — and press Enter.
Enter a domain name (e.g. example.com), or an IP address for PTR and blacklist look ups.
Toggle "Also look up blacklist status" above to include a DNSBL look up alongside your search.
Your last 20 look ups are saved in the History panel so you can revisit them anytime.

Why it matters

Being listed on even one widely-used blacklist can cause a meaningful share of your outgoing email to be silently rejected or sent straight to spam, regardless of how well-configured your SPF, DKIM and DMARC are. Checking regularly — especially after noticing a drop in email deliverability — helps you catch a listing early and start the delisting process before it does more damage.

Examples

After migrating to a new mail server IP (especially a shared cloud IP), look it up before relying on it for production email — previous tenants can leave a bad reputation behind.
If recipients report your emails are going to spam, a blacklist look up is one of the fastest ways to rule out (or confirm) IP reputation as the cause.
Each blacklist has its own delisting process — being listed doesn't mean permanently blocked, but it does require action.