Mailcheck - An application to clean your subscription list from bounces, and enrich data with the customers

Mailinator - Any Inbox. Any Time.

mailfloss - Bulk email verification for busy businesses and email marketers. Put your email validation on autopilot. One-time, 60-second setup, no developers needed. Get your emails delivered to real people and maximize your email ROI.

TempMail.altmails - Disposable temporary email addresses

Reacher - Check if an email exists without sending any email.

Harakirimail - Harakirimail is a free disposable email service. Just send email to anythingyouwant@harakirimail.