Catch-All Domain Detector
Catch-all domains accept any address; bounce verification looks clean but mail goes to a black hole. This tool flags the pattern.
# Get the MX
dig MX example.com +short
# Connect to the lowest-priority MX
telnet $(dig MX example.com +short | sort -n | head -1 | awk '{print $2}') 25
# In the SMTP dialog:
HELO yourdomain.com
MAIL FROM: <test@yourdomain.com>
RCPT TO: <xyzabc123nonexistent@example.com>
# If the server returns 250 OK → catch-all
# If the server returns 550/551 unknown → not catch-allCatch-all domains accept any address, so list-verification tools report "valid" for addresses that don't actually exist. Mail to a non-existent address on a catch-all domain goes to /dev/null without bouncing. your reply rate looks zero with no diagnostic signal.
Checked. Now see who reads what you send.
A clean setup gets your email delivered. Outsolvi covers what happens next: every open graded as a person or a machine, who clicked and who replied, and follow-ups that stop when someone answers. From $7/user/mo billed yearly, 14-day free trial.
Start free trialGenerates the SMTP session you run yourself to detect a catch-all domain. It builds the exact commands for testing an obviously-fake address (e.g. xyzabc123nonexistent@) and explains how to read the reply: if the server accepts it, the domain is catch-all and your bounce-verification tool is lying to you. The test runs from your terminal, not from this page.
Before trusting any bounce-verification result. Especially before sending to executive lists where catch-all is common.
FAQ
Why do companies run catch-all?+
To avoid losing mail addressed to typoed addresses, or to capture mail to former employees. Common at small companies; rare at large enterprises.
Keep going
Articles, glossary entries, and other tools on the same topic.
Nate built Outsolvi after watching every email-tracking tool he had ever used lie to him about opens. Outsolvi grades every open as a person or a machine, in Outlook and Gmail, so the number on the dashboard is one a rep can actually act on.
We update these pages when the underlying mechanics change. new mailbox-provider rules, new tracker behavior, new measurement gaps. The dates above are real revisions, not auto-touches.