The typeof Operator in JavaScript

The typeof Operator in JavaScript

Ferenc Almasi β€’ 2020 December 10 β€’ πŸ“– 1 min read

In JavaScript, the typeof operator can be used for getting the data type of its operand as a string:

// The typeof operator is used for getting
// the type of its operand:

// This will return "string"
typeof '1'

// This will return "number"
typeof 1

// This will return "number"
typeof NaN

// This will return "boolean"
typeof true

// This will return "undefined"
typeof undefined

// This will return "symbol"
typeof Symbol()

// This will return "object"
typeof []

// This will return "object"
typeof null
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Note that the type of NaN is a number. Also the type of null is an object. If you are interested in the history of why null is an object, I highly recommend checking out the below article from 2ality:

The history of "typeof null"

What is the typeof operator in JavaScript?
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