Find the addresses that will bounce
We ask the mail server whether the mailbox exists, without sending an email. Addresses that would bounce come back Undeliverable with the reason.
- Six checks on every address
- A plain reason with every result
- Slow servers never cost a second credit
- 200 free credits, no card
Examples
What it looks like in your results
Result rows with the category and the reason you will see.
How it works
How we detect it
This check runs on every address, as part of the same credit.
- 01
Run the earlier checks
Format, typo, disposable, role, domain and catch-all checks run first.
- 02
Ask the mail server
We ask whether this exact mailbox exists, and stop before anything is sent.
- 03
Return the answer
Undeliverable with a reason, or Risky if the server won't confirm either way.
What to do
What to do with these addresses
Every result comes with the reason, so you can decide row by row.
Remove before sending
Bounces hurt your sender reputation, so take these out first.
Add to a suppression list
Filter Undeliverable rows and block them in your sending tool.
Recheck unconfirmed ones later
Servers that won't confirm today may answer in a few weeks.
Related checks
Part of all six checks
Every address goes through all of them, in order.
Catch-all detection
Some domains say yes to any address, so no one can confirm the mailbox.
Learn moreFAQ
Bounce detection questions
Short answers about this check.
Still have a question? Talk to us.
Check your list before you send it
Start with 200 free credits. Pay per credit after that.