Check if a key exists in an object

JavaScript performance comparison

Test case created by Adam Drago

Preparation code

Benchmark.prototype.setup = function() {
    var obj = { a: true, b: true, c: true, d: true, e: true, f: true };

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Testing in unknown unknown
Test Ops/sec
in operator
if ("b" in obj) {

array notation
if(obj["b"] !== undefined) {


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