Email Validator by Sidemail - Free email address validator (inc. SMTP deep check)

Hi Hunters!

I'm Kristyna, maker of Sidemail. I'm happy to share with you what we've been building.

If you're sending marketing or ad emails, you'll love this.

Nothing ruins a campaign like poor deliverability. Bad email addresses drive up bounces, hurt your sender reputation, and lower open/reply rates.

Email validator is what helps you avoid this.

But most of the tools like this hide behind signups and paywalls.

We made a free, no-signup, in-browser checker you can use fast.

Upload a CSV with the email addresses you want to validate, and it performs checks:
- Syntax – Confirms correct proper email format (name@domain).
- Domain & DNS – Verifies the domain exists and resolves.
- MX records – Verifies the domain can receive mail.
- SMTP handshake (optional) – Checks the mail server accepts the recipient.
- Disposable domains – Flags temporary inbox providers that can hurt deliverability lists.
- Common typos – Catches mistakes and suggests fixes.

Want to verify a whole list? Try our Email list validation tool – https://sidemail.io/tools/email-...

If you have any questions or thoughts to share, please do tell.

Thank you!
Kristyna 💙

Congrats on the launch

With PH traffic rolling in, how are you thinking about turning early users into reviews and long-term trust?