Benchmark: tagName vs instanceof

Script Preparation code:

var xs = [];
var n = 0;

for (let i = 0; i < 1000; ++i) {
  xs[i] = (Math.random() > .5) ? document.createElement(`div`) : document.createElement(`span`);
};

Tests:

instanceof
n += ((xs[(Math.random() * 1000)|0]) instanceof HTMLDivElement)|0;
tagName
n += (xs[(Math.random() * 1000)|0].tagName === `DIV`)|0;
nodeName
n += (xs[(Math.random() * 1000)|0].nodeName === `DIV`)|0;
localName
n += (xs[(Math.random() * 1000)|0].localName === `div`)|0;
__proto__
n += ((xs[(Math.random() * 1000)|0]).__proto__ === HTMLDivElement.prototype)|0;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
instanceof
tagName
nodeName
localName
__proto__

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 9 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:125.0) Gecko/20100101 Firefox/125.0

Browser/OS: Firefox 125 on Windows

View result in a separate tab

Test name	Executions per second
instanceof	13574700.0 Ops/sec
tagName	21458350.0 Ops/sec
nodeName	25919630.0 Ops/sec
localName	24169060.0 Ops/sec
__proto__	23534750.0 Ops/sec

tagName vs instanceof (version: 0)

Comparing performance of: instanceof vs tagName vs nodeName vs localName vs proto

Created: 4 years ago by: Registered User

Jump to the latest result

instanceof

tagName

nodeName

localName

proto

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

tagName vs instanceof (version: 0)

Comparing performance of: instanceof vs tagName vs nodeName vs localName vs __proto__

Created: 4 years ago by: Registered User

Jump to the latest result

instanceof

tagName

nodeName

localName

__proto__

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Comparing performance of: instanceof vs tagName vs nodeName vs localName vs proto

proto