VerifyEmail.io

VerifyEmail.io runs multi-layer checks on email addresses to spot invalid, disposable, and risky addresses before they hit your list. The API validates format, confirms domain existence, checks MX records, and attempts SMTP verification to verify the mailbox actually exists.

It fits marketers on tight budgets since the free tier covers genuine use cases. It works well alongside your main platform if you want a lightweight, straightforward validation API without complex workflows or bulk processing overhead.