Javascript performance consideration. Is dot operator faster than subscript notation?

Question

Is dot operator faster than subscript notation?

var obj = {x: \'5\'};
obj.x = \'some value\';
obj[\'x\'] = \'some value\';

Answer 1

Not anything incredibly worrying. Acessing variables by window or eval are significantly slower though.

http://jsperf.com/dot-vs-square-bracket/5