Skip to content

Verify by provider

Every mailbox provider speaks its own SMTP dialect

Gmail, Outlook.com, Yahoo, iCloud, Google Workspace and Microsoft 365 each word their answers differently and each has its own limits. RocketVerifier has rules for every one of them.

Quick answer

To verify an address, RocketVerifier checks syntax and DNS, identifies the mail provider from its MX records, then asks that provider over SMTP whether the mailbox accepts mail, stopping before any email is sent. Each provider gets its own reply rules, pacing and rate budget, so a missing mailbox is caught and a rate limit or IP block is never mistaken for a bad address.

Provider guides

Built for every provider

Why provider rules decide accuracy

A generic verifier reads every SMTP reply the same way. That turns rate limits into invalid addresses and missing mailboxes into unknowns.

  • Per-provider rate budgets

    Each IP has its own budget per receiving provider, with automatic back-off after a deferral, so Gmail, Outlook and Yahoo keep answering instead of blocking.

  • Provider-specific reply parsing

    Google, Microsoft, Yahoo, Mimecast, Proofpoint and Barracuda each word their SMTP replies differently. Each gets its own rules, so a policy block is never mistaken for a missing mailbox.

Start free

100 free credits · No card required

Verify every provider with one tool

Gmail, Outlook, Yahoo, iCloud, Workspace, Microsoft 365 and custom servers, each with its own rules. Start with 100 free credits.

Start free See pricing

100 free credits · No card required · Credits never expire