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gia ly bui
gia ly bui

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I Built a Free Email Validator API — SMTP Handshake Explained

Sending to invalid emails kills deliverability. Most validators cost $20-50/month.

Built my own. Three checks: syntax (regex), MX record (DNS), SMTP handshake (connect to mail server, ask "does this mailbox exist?", disconnect).

Stack: FastAPI + Python stdlib. Zero deps. $0/month. 1,000 free/month.

Search "Email Validator API" on RapidAPI.

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