Parsley
Validate your forms, frontend, without writing a line of javascript
...No need to write even a single JavaScript line for simple form validation. Parsley is now smarter, it automatically detects your forms' modifications and adapts its validation accordingly. Simply add, remove or edit fields, Parsley validation will follow! Parsley is shipped with more than a dozen useful validators. If not enough, use the awesome Parsley extra Ajax validator or tons of other extended validators provided by the community. Parsley strongly focuses on #UI and #UX. Override almost every Parsley default behavior to fit your exact needs. ...