JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>

<div class="bootstrap-timepicker">
  <input id="timepicker4" type="text" class="form-control" name="startingTime" value="00:00" required/>
</div>

JavaScript

$(document).ready(function(){
    $('[id^=timepicker4]').keypress(validateNumber);
});

function validateNumber(event) {
    var key = window.event ? event.keyCode : event.which;

    if (event.keyCode === 8 || event.keyCode === 46
        || event.keyCode === 37 || event.keyCode === 39) {
        return true;
    }
    else if ( key < 48 || key > 57 ) {
        return false;
    }
    else return true;
};