32 lines
1.1 KiB
Markdown
32 lines
1.1 KiB
Markdown
---
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title: What's the difference between Object.is() and the triple equals operator in JavaScript?
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shortTitle: Object.is() vs triple equals operator
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type: question
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tags: javascript,object,type
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author: chalarangelo
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cover: rocky-mountains
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excerpt: "`Object.is()` and the triple equals operator (`===`) can both be used for equality checking in JavaScript, but when should you use each one?"
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firstSeen: 2021-03-04T11:00:00+02:00
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lastUpdated: 2021-06-12T19:30:41+03:00
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---
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If you want to check equality in JavaScript, there are two comparison operators, which are explained in depth in a previous [article](/blog/s/javascript-equality).
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Very briefly, the double equals operator (`==`) only compares value whereas the triple equals operator (`===`) compares both value and type. But there is also a third option, `Object.is()`, which behaves the same as the triple equals operator with the exception of `NaN` and `+0` and `-0`.
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Here are some examples for additional clarity:
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```js
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{} === {}; // false
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Object.is({}, {}); // false
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1 === 1; // true
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Object.is(1, 1); // true
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+0 === -0; // true
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Object.is(+0, -0); // false
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NaN === NaN; // false
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Object.is(NaN, NaN); // true
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```
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