TrustIP · NETWORK DIAGNOSTICS

IP Blacklist Checker

Check your sending server’s IPv4 address against public email blocklists. Use the sending IP from your SMTP bounce or mail logs.

Check a sending IP

Live lookups require JavaScript. The notes below are available without running a lookup.

Choose an IP tool

IP Lookup Find the ASN, network operator and estimated location behind an address.Proxy IP Checker Compare proxy, hosting and mobile flags with Tor exit-list membership.

What to do with a blocklist result

Listed
Compare the list name with the one in your SMTP rejection. Open the list operator’s site to verify the listing and follow its removal process.
Not listed
That list returned no listing during this lookup. Email delivery can still depend on other lists, domain reputation and mail authentication.
Query failed or unavailable
An unavailable list has no result to interpret. Retry the query or check with the list operator. This tool queries IPv4 mail blocklists.

Troubleshooting guides

How to remove an IP from an email blocklist →Check your mail server’s PTR record →

Methodology and data sources