Toggle navigation
MeasureThat
.net
Create a benchmark
Tools
Feedback
Feature Requests
FAQ
Register
Log In
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
Embed
Embed Benchmark Result
<iframe src="https://measurethat.net/Embed?id=511407" width="100%" height="500px"></iframe>
Run details:
User agent:
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:123.0) Gecko/20100101 Firefox/123.0
Browser:
Firefox 123
Operating system:
Windows
Device Platform:
Desktop
Date tested:
2 years ago
Benchmark engine:
Benchmark.js
string is undefined
377.5M/s
undefined is undefined
329.4M/s
typeof undefined is undefined
313.1M/s
typeof string is undefined
311.7M/s
View exact numbers
Test name
Executions per second
✓
string is undefined
377,545,408 Ops/sec
undefined is undefined
329,374,560 Ops/sec
typeof undefined is undefined
313,058,304 Ops/sec
typeof string is undefined
311,730,432 Ops/sec
Tests:
typeof string is undefined
typeof "not undefined" === "undefined"
typeof undefined is undefined
typeof undefined === "undefined"
string is undefined
"not undefined" === undefined
undefined is undefined
undefined === undefined