The typeof Operator in JavaScript
Ferenc Almasi • 2020 December 10 •
1 min read
In JavaScript, the typeof operator can be used for getting the data type of its operand as a string:
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// 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 nullNote 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:
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