JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" name="fname" id="fname" />

JavaScript

$("#fname").on("blur", function() {
    if ( $(this).val().match('^[a-zA-Z]{3,16}$') ) {
        alert( "Valid name" );
    } else {
        alert("That's not a name");
    }
});