MeasureThat.net

Run results for: is variable undefined? typeof variable === "undefined" vs variable === undefined

Comparing whether checking is (typeof variable === "undefined") is faster than (variable === undefined)

Go to the benchmark
Run details:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36
Chrome 98
Windows
Desktop
2 years ago
Test name Executions per second
typeof string is undefined 891083520.0 Ops/sec
typeof undefined is undefined 6854603.0 Ops/sec
string is undefined 4624114.5 Ops/sec
undefined is undefined 2864904.0 Ops/sec
Tests:

  • typeof string is undefined

  • typeof undefined is undefined

  • string is undefined

  • undefined is undefined

;