JSFiddle - React, Tailwind, and code Playground

JavaScript

function validate( input ) {
    var date = new Date( input );
    input = input.split( '/' );    
    return date.getMonth() + 1 === +input[0] && date.getDate() === +input[1] && date.getFullYear() === +input[2];
}

console.log( validate( '2/1/1983' ) );
console.log( validate( '2/29/1983' ) );
console.log( validate( '2/29/1984' ) );