isNaN() vs n !== n

JavaScript performance comparison

Test case created by gfx

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var nan = NaN;
    var val = 100;
};
</script>

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Testing in unknown unknown
Test Ops/sec
isNaN
if (isNaN(nan)) { /* NaN */ }
if (isNaN(val)) { /* NaN */ }
pending…
v !== v
if (nan !== nan) { /* NaN */ }
if (val !== val) { /* NaN */ }
pending…

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