CPU benchmark

cpubenchmark.js

function cpuBenchmark() {
	var blob, worker, work;

	function onMessage() {
		var i,
			startTime,
			amount = 100000000;

		// IE11 doesn't have window.performance exposed inside workers
		if ( !self.performance ) {
			postMessage( false );
			return;
		}

		startTime = performance.now();

		for ( i = amount; i > 0; i-- ) {
			// empty
		}

		postMessage( Math.round( performance.now() - startTime ) );
	}

	work = 'onmessage = ' + String( onMessage );

	blob = new Blob( [ work ], { type: 'application/javascript' } );
	worker = new Worker( URL.createObjectURL( blob ) );

	worker.onmessage = function ( e ) {
		console.log( e.data );
		worker.terminate();
	};

	worker.postMessage( false );
}

cpuBenchmark();