MailCull is an email verification tool for teams that send real volume and get blamed when a list bounces. Most validators hand you "valid" or "invalid" and refuse to explain it. MailCull gives you the receipt: the actual SMTP reply, the MX record, and a confidence score behind every verdict, so a deliverable is one you can defend and a risky tells you why.
Every address is returned as one of four clear states, deliverable, risky, undeliverable, or unknown, each with a reason in plain English rather than a number you have to trust. Catch-all and accept-all domains are flagged with the behaviour that makes them risky, instead of being quietly marked valid and bouncing at send time.
Verify a whole list by uploading a CSV, or check a single address instantly. Deep scan probes mailboxes at the SMTP level for a sharper verdict, and it is included on the free plan, not locked behind an upgrade. The AI Analyst reads the evidence for any result and explains the conclusion in a sentence. Real-world accuracy lands in the 91 to 93 percent range, and we publish how we measure it.
Pricing is one flat price with a unified monthly credit pool. No per-pack math, no surprise overages, and no charge for unknowns. There is a developer API and a first-party MCP server, so you can verify from your own app or from AI tools like Claude and Cursor.