Despite the advancement in technologies, email remains to be the most trusted mode of business communication. Companies use emails to generate leads, increase engagements, make transactions, and track consignments and orders. Email validation APIs are employed by companies to verify the validity of an email address before sending any message. After reviewing all the Email Verification APIs, ten APIs were found to be worth mentioning, including ZeroBounce API, Email Check Invalid or Disposal Domain API, DeBounce Email Verification API, Bouncer API, and others. These APIs are best suited for various purposes such as reducing bounce rates, blocking disposable emails, checking validity in huge email listings, cleaning email listing to avoid bounce rates, greylisting harmful emails, identifying fake emails during sign-ups, detecting spam traps and honeypots, preventing blacklisting, collecting valid email addresses, distinguishing generic from corporate and organizational emails. The pricing of these APIs varies from free basic plans to paid packages with different tiers and costs, ranging from $15 per month to $195 per month.