What are some alternatives?
When comparing Impressionwise and Advanced Email Verifier, you can also consider the following products
Email Verifier - Email verifier app lets you verify email.
EmailRecon - Real-time email adddress validation and verification. The EmailRecon cloud list verification tool allows you to clean your email lists with a single click.
NoBounce Email List Cleaner - Email list validation & cleaning maximizes the efficiency of your email marketing campaigns and protects your email sender reputation.
NeverBounce - Real-time email verification and cleaning to ensure emails never bounce.
useBouncer - The most intelligent email checker, that lets you focus on valuable relationships! Verify email address with simple App or easy-to-integrate API.
Emailmarker - The Most Reliable and Accurate Way to Improve Your Email List Deliverability.