The digital world is rapidly growing into a trillion-dollar industry, with the internet being used for daily transactions, knowledge, and searching for virtually anything. However, despite the benefits of digitization, there are also several vices associated with it, including online spamming, hacking, and fraud, which result in millions of dollars lost every year. To combat these issues, developers have created mechanisms such as spam APIs to curb spam. These APIs help detect fake email adverts by providing spam scores through machine learning technologies. Some of the top-rated spam APIs include OOPSpam Spam Filter API, Nexmo Number Insight API, Verimail API, ViewDNS API, Get Email Information API, and Regulus Email Validation API. Each API has its unique features, pricing plans, and popularity scores, making it essential to select the best one for specific needs. For instance, OOPSpam Spam Filter API is best for detecting fake email adverts, while Nexmo Number Insight API is ideal for checking phone number validity and information. Similarly, Verimail API is suitable for ensuring maximum email delivery rates, and ViewDNS API is perfect for sourcing DNS tools. The most popular spam APIs are OOPSpam Spam Filter API with a popularity score of 9.4/10, followed by Nexmo Number Insight API with a score of 8.4/10. Understanding the features, pricing plans, and popularity scores of these APIs can help users make informed decisions when selecting the best spam API for their specific needs.