TOAST UI Calendar is A JavaScript schedule calendar that is full featured. Now your service just got the customizable calendar.

<!-- HTML -->
<div id="calendar" style="height: 800px;"></div>

<!-- JavaScript -->
<script >
	var calendar = new tui.Calendar('#calendar', {
		defaultView: 'month',
		taskView: true,
		template: {
			monthDayname: function(dayname) {
				return '<span class="calendar-week-dayname-name">' + dayname.label + '</span>';
			}
		}
	});
</script>