APILayer
We offer a hassle-free API Marketplace. It boosts your app’s capabilities without worrying about scalability and stability.
The API to use it is simple and does what you need it to do without the frills that most others solutions come with. Returns just a simple JSON string that you can use how you want. It is fast on the front end (browsers) and the price is competitive. It is good for the validation of emails to do perfect email marketing, as it helps in removing unnecessary spam emails from the list.