Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.71 Safari/537.36
Chrome 97
Mac OS X 10.15.7
Desktop
3 years ago
Test name Executions per second
typeof string is undefined 693784768.0 Ops/sec
typeof undefined is undefined 6141472.0 Ops/sec
string is undefined 6504195.5 Ops/sec
undefined is undefined 3073593.8 Ops/sec
Tests:
  • typeof string is undefined

    AخA
     
    typeof "not undefined" === "undefined"
  • typeof undefined is undefined

     
    typeof undefined === "undefined"
  • string is undefined

     
    "not undefined" === undefined
  • undefined is undefined

     
    undefined === undefined