JavaScript Form Validator - Version 3.1.0 Most web forms require form input validations to prevent the user from entering bad data. JavaScript is commonly used for client side form validations. It gives the response immediately. But, when there are many forms in the project and when the forms are long, writing the form validations becomes a daunting, repetitive task.Save yourself from repetitively coding JavaScript form validations. The JavaScript Form validator script has almost all commonly required form validations built-in. Using this script, adding form validations to your form is quick and easy. The code is general, simple, extensible and free!