The native HTML5 validation feature is not enough.
We also recommend you use a JavaScript library to extend and enhance the default form validation functionalities for better user experiences on modern web design.
In this post, you’ll find a list of the 10 best and most downloaded JavaScript Form Validation libraries (without any 3rd dependencies such as jQuery) to validate your HTML form with custom error messages, CSS styles, validation rules, and more. Enjoy.
Originally Published Feb 10, 2018, updated Jan 03 2026