Email Verification Glossary
Short, plain definitions of the terms you'll see in verification results, with a free tool for each where one exists.
Short answer
A catch-all domain accepts mail for any address, so a normal check can't tell whether a specific mailbox exists. A role address (info@, sales@) reaches a shared inbox. A disposable email is a throwaway inbox. Bounce rate is the share of sent emails that fail; keep it under 2% for cold email.
Terms
- Catch-all (accept-all)
- A domain set to accept mail for every address. A deeper check like Verify+ can help, but some addresses remain Risky.
- Role address
- A shared address such as info@, sales@ or support@. Deliverable, but replies and engagement are lower.
- Disposable email
- A temporary inbox from a throwaway provider. Check one free with the disposable email checker.
- Hard bounce
- A permanent failure: the mailbox or domain doesn't exist. Remove these immediately.
- Bounce rate
- Bounced emails divided by emails sent. Under 2% is safe for cold email.
- MX record
- The DNS record that says which server receives a domain's mail. No MX means no mail. Check with MX lookup.
- SPF, DKIM, DMARC
- DNS records that prove you're allowed to send for your domain. Check yours with the DMARC & SPF checker and DNS health check.
- Syntax check
- Confirms an address is formatted correctly. Free with the syntax checker.
Frequently asked questions
What does catch-all mean in email verification?
The receiving domain accepts mail for any address, so the server can't confirm whether a specific mailbox exists. These come back risky until a deeper second pass settles them.
Are role addresses like info@ safe to email?
They usually deliver, but they reach shared inboxes with lower reply rates. Most cold emailers keep them out of the main campaign.
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