Info

Checking the real performance difference for the various javascript loops patterns.

Preparation code

 
<script>
  Benchmark.prototype.setup = function() {
    var bigArray = [];
    var j =0;
    for(var i=0; i < 1000; i++){
        bigArray.push(i);
    }
  };
</script>

Test runner

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for(var i=0; i < bigArray.length; i++){
    j++;
}

for(var i= bigArray.length; i--;){
    j++;
}

for(var i=0; i < bigArray.length; ++i){
    j++;
}

var length = bigArray.length;
for(var i=0; i < length; i++){
    j++;
}

var length = bigArray.length;
while(length--){
    j++;
}

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published by Arash Milani on 18th January 2013
• Revision 2: published on 19th January 2013
• Revision 3: published on 21st January 2013
• Revision 5: published by Fabrice Daugan on 27th January 2013
• Revision 6: published on 28th January 2013
• Revision 7: published on 28th January 2013
• Revision 9: published on 30th January 2013
• Revision 10: published on 30th January 2013
• Revision 11: published on 30th January 2013
• Revision 12: published on 30th January 2013
• Revision 14: published on 2nd February 2013
• Revision 15: published on 2nd February 2013
• Revision 16: published on 2nd February 2013
• Revision 17: published on 10th February 2013
• Revision 18: published by Dmitriy on 13th February 2013
• Revision 19: published on 13th February 2013
• Revision 20: published by Niels Boehm on 14th February 2013
• Revision 21: published on 15th February 2013
• Revision 22: published on 15th February 2013
• Revision 23: published on 16th February 2013
• Revision 24: published on 18th February 2013

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