Try emailverifier.com their accuracy is unparalleled. If what you need is accurate results and you care about losing potential customers check the service out Email Verification will result in a highly deliverable list, removing hard bounces and syntactically wrong emails, Domain Invalid domains and all emails not responding to a check. Lastly it will group them into Risky, Valid , Invalid so you would know where to aim.
Another one great solution is TrueMail (https://truemail.io) Convenient, easy and fast email verification tool. By the way, it has free trial and you can verify your first 1000 emails for free.
Here are two popular options. Both offer free trials, so you can test them out before committing. ZeroBounce: They offer high accuracy and features like bounce rate reduction. They have various plans, so you can find one that fits your budget. NeverBounce: Another user-friendly option with good deliverability rates. They provide different tiers with varying numbers of verifications.