Run results for: Undefined testing including ! - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/110.0

Browser: Firefox 110

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
typeof x === "undefined"	1735008768.0 Ops/sec
x === undefined	1734316800.0 Ops/sec
x == undefined	1694856064.0 Ops/sec
x == null	1769316736.0 Ops/sec
!x	1670290816.0 Ops/sec

Script Preparation code:

var x;

Tests:

typeof x === "undefined"
typeof x === "undefined"
x === undefined
x === undefined
x == undefined
x == undefined
x == null
x == null
!x
!x