jsBenchmarker

Source of "isnan"

Benchmarker().compare({ attempts:5, times:3e4, wait:1e3 },{
	isNaN:function(){
		!isNaN(25);
	},
	Typeof:function(){
		typeof 25 == 'number';
	},
	Constructor:function(){
		(25).constructor == Number;
	},
	isNaN_false:function(){
		!isNaN('abc');
	},
	Typeof_false:function(){
		typeof 'abc' == 'number';
	},
	Constructor_false:function(){
		('abc').constructor == Number;
	}
});

/**
 * Conclusion
 *	isNaN is faster in FF, constructor is faster in IE.
 */