The jQuery UI Datepicker is widely used plugin that gives you datepicker functionality to your webpages. You can easily customize the date format, range, language and and many more.
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Bootstrap Datepicker is the best alternative of jQuery ui datepicker, It will provides you almost all features that jQuery ui datepicker provide but it comes in better appearence than jquery ui datepicker, There is some how-tos to get strated with Bootstrap datepicker .