What are some alternatives?
When comparing Impressionwise and Email Verifier, you can also consider the following products
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.
Email List Verify - The Fastest Way to Improve Email List Deliverability and ROI
useBouncer - The most intelligent email checker, that lets you focus on valuable relationships! Verify email address with simple App or easy-to-integrate API.
NeverBounce - Real-time email verification and cleaning to ensure emails never bounce.
NoBounce Email List Cleaner - Email list validation & cleaning maximizes the efficiency of your email marketing campaigns and protects your email sender reputation.
ZeroBounce - Removes invalid emails from your list to prevent email bounces from ruining your deliverability.