i++ vs ++i

JavaScript performance comparison

Revision 2 of this test case created


The hello world books of programming always start you off with i++, however did you know that i++ comes with a bit of overhead? that's because before you can increment i under the hood a new copy of i must be created. Using ++i you don't need that extra copy. i++ will return the current value before incrementing i. ++i returns the incremented version i. This test is to demonstrate that it's faster to use ++i. Get ready get set update your code!

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Testing in unknown unknown
Test Ops/sec
100000 iterations of ++i
for (var i = 0; i < 100000; ++i) {}
100000 iterations of i++
for (var i = 0; i < 100000; i++) {}

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1 comment

BStramke commented :

So, there seems to be no difference at all as browsers have adapted to that behavior...

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