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- http://www.accuwebhosting.com/blog/2014/09/29/top-10-email-list-validation-verification-services-compared/
- https://www.marketingtechblog.com/verify-email-lists/
- Usually 1 penny a contact.
- We suggest:
- Neverbounce
- Validity (formerly BriteVerify (- easiest to use if you're in a pinch)
- TowerData (strong quality)
- Experian (formerly LeadSpend)
- Kickbox.io
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