Highlight Today’s date in SharePoint 2013 Calendar List

Step 1: Go to your Calendar list, Edit page and add Script Editor Web Part to it.

Step 2: Paste the below code to Script Editor Web Part

Code:

<script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.8.3.min.js"></script>

<script type="text/javascript">

$(function(){

    //append text

    var originText=$(".ms-acal-today").find("nobr").text();

    $(".ms-acal-today").find("nobr").text(originText+"Today");

    //change the background

    $(".ms-acal-today").css("background-color","yellow");

});

</script>