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Bulk email verification with full SMTP server responses
Verifies that a given email is real.
Verifier API is a free Email API that requires apiKey authentication, is served over HTTPS and supports CORS, so it can be called from the browser.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Bulk email verification with full SMTP server responses
Email for AI agents: send email, receive replies as threads, with per-key send limits and approvals
A service that provides solutions relating to marketing and/or transactional email and/or SMS
Yes. The Verifier API is listed in the Email category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Verifier API uses apiKey authentication, so you need to register for credentials before making requests.
Yes. The Verifier API supports CORS, so front-end JavaScript can call it directly.
Yes. The Verifier API is served over HTTPS, so it's safe to use in production.