In JavaScript, beyond numeric data, the Number type is also used to represent special values like NaN, Infinity, or -Infinity.

Converting expressions to numbers

To convert a string or an expression into an integer or a floating point number, you can use the global built-in Number function:

Number(expression)

Note that if the value can't be converted into a valid number, the Number function will return NaN.

Example

In this example, all values will be converted to numbers:

Number(1)       // 1Number('123')   // 123Number(null)    // 0Number(true)    // 1Number(false)   // 0

However, these values will be converted to NaN:

Number('text')      // NaNNumber(undefined)   // NaN

Converting strings to integers