JSFiddle - React, Tailwind, and code Playground

HTML

<input size="12" id="inputField" name="inputField"  autofocus="" type="date"     onblur="return dateValidate(this)"/>

JavaScript

function dateValidate(inputField)
 {
    var pickeddate =  new Date(inputField.value);
    var todayDate =  new Date();
    if( pickeddate > todayDate )
    {
      return true;
    }
    else
    {
      alert("Enter a valid Date");
    } 
}