Question: Is there a form service that offers built-in spam blocking and data validation using machine learning and server-side checks?

If you need a form service that's got built-in spam blocking and data validation, including machine learning and server-side checks, Formspree is a good option. It's got good spam protection options, including automated filtering and easy Captchas, custom rules and reCaptcha integration. Formspree also has machine learning-based data validation and a variety of built-in tools for analyzing and exporting form submissions.

Another good option is Akismet, which has a strong focus on advanced spam protection with real-time machine learning and AI. It's got 99.99% accuracy for blocking spam, which can dramatically improve user experience and cut down on administrative work. Akismet works on a variety of platforms and offers flexible API options, so it's good for a wide range of needs.

If you're using WordPress and Shopify, Human Presence is a good option for blocking spam and bot activity. The service uses proprietary behavior analysis to protect unlimited forms on either platform, and it's designed to keep the user experience frictionless. It offers a variety of pricing options, including a free trial for Shopify sites, so it's good for businesses of all sizes and budgets.

Last, CHEQ is a full-on security platform that uses a combination of cutting-edge client and server-side techniques to thwart automated and human-powered threats. With tools like CHEQ Form Guard and CHEQ On-Site Security, it's got a lot of ways to block bot activity and protect data, so it's a good option for businesses that want a security service that's got everything.