Run results for: == null (with implicit conversion) vs (=== null || === undefined) vs util function

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser: Chrome 120

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
== null	1649292.1 Ops/sec
=== null \|\| === undefined	582183.1 Ops/sec
== null (via util func)	949545.0 Ops/sec
=== null \|\| === undefined (via util func)	563454.2 Ops/sec
=== null \|\| === undefined \|\| === ""	489681.3 Ops/sec
=== null \|\| === undefined \|\| === "" (via utility func)	564379.1 Ops/sec
== null with complex object or array only	2256045.2 Ops/sec
== null with complex object or array only (via utility func)	564580.2 Ops/sec

Script Preparation code:

var o = {abc:'Hello', prop2: 456, nested: {prop3: 'TheId'}};
var a = [[1,2,3],[36.664,53366]];
var u = undefined;
var n = null;
var d = 256.6353;
var f = NaN;
var b = true;
var s = 'a very long string 1233 all the way until the end';
//let m = new Symbol('ASymbol');
var l = false;
function i1(v) { return v == null; }
function i2(v) { return v === null || v === undefined; }
function i3(v) { return v === null || v === undefined || v === ''; }

Tests:

== null
if(o == null) l = true; if(a == null) l = true; if(u == null) l = true; if(n == null) l = true; if(d == null) l = true; if(f == null) l = true; if(b == null) l = true; if(s == null) l = true;
=== null || === undefined
if(o === null || o === undefined) l = true; if(a === null || a === undefined) l = true; if(u === null || u === undefined) l = true; if(n === null || n === undefined) l = true; if(d === null || d === undefined) l = true; if(f === null || f === undefined) l = true; if(b === null || b === undefined) l = true; if(s === null || s === undefined) l = true;
== null (via util func)
if(i1(o)) l = true; if(i1(a)) l = true; if(i1(u)) l = true; if(i1(n)) l = true; if(i1(d)) l = true; if(i1(f)) l = true; if(i1(b)) l = true; if(i1(s)) l = true;
=== null || === undefined (via util func)
if(i2(o)) l = true; if(i2(a)) l = true; if(i2(u)) l = true; if(i2(n)) l = true; if(i2(d)) l = true; if(i2(f)) l = true; if(i2(b)) l = true; if(i2(s)) l = true;
=== null || === undefined || === ""
if(o === null || o === undefined || o === '') l = true; if(a === null || a === undefined || a === '') l = true; if(u === null || u === undefined || u === '') l = true; if(n === null || n === undefined || n === '') l = true; if(d === null || d === undefined || d === '') l = true; if(f === null || f === undefined || f === '') l = true; if(b === null || b === undefined || b === '') l = true; if(s === null || s === undefined || s === '') l = true;
=== null || === undefined || === "" (via utility func)
if(i3(o)) l = true; if(i3(a)) l = true; if(i3(u)) l = true; if(i3(n)) l = true; if(i3(d)) l = true; if(i3(f)) l = true; if(i3(b)) l = true; if(i3(s)) l = true;
== null with complex object or array only
if(o == null) l = true; if(a == null) l = true; if(o == null) l = true; if(a == null) l = true; if(o == null) l = true; if(a == null) l = true; if(o == null) l = true; if(a == null) l = true;
== null with complex object or array only (via utility func)
if(i3(o)) l = true; if(i3(a)) l = true; if(i3(u)) l = true; if(i3(n)) l = true; if(i3(d)) l = true; if(i3(f)) l = true; if(i3(b)) l = true; if(i3(s)) l = true;

Run results for: == null (with implicit conversion) vs (=== null || === undefined) vs util function

== null

=== null || === undefined

== null (via util func)

=== null || === undefined (via util func)

=== null || === undefined || === ""

=== null || === undefined || === "" (via utility func)

== null with complex object or array only

== null with complex object or array only (via utility func)