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Other References

CSSStyleDeclaration JS Conversion


JavaScript Number()

Examples

Convert booleans and dates to a number:

Number(true);
Number(false);
Number(new Date());
Try it Yourself »

More examples below.


Description

The Number() method converts a value to a number.

If the value cannot be converted, NaN is returned.

Notes

For booleans, Number() returns 0 or 1.

For dates, Number() returns milliseconds since January 1, 1970 00:00:00.

For strings, Number() returns a number or NaN.


Syntax

Number(value)

Parameters

Parameter Description
value Optional.
A JavaScript value (variable).

Return Value

Type Description
A numberReturns the value as a number.
If the value cannot be converted to a number, NaN is returned.
If no value is provided, 0 is returned.


Browser Support

Number() is an ECMAScript1 (ES1) feature.

ES1 (JavaScript 1997) is fully supported in all browsers:

Chrome Edge Firefox Safari Opera IE
Yes Yes Yes Yes Yes Yes

More Examples

Convert different numbers to a number:

Number(999);
Number("999");
Number("999 888");
Try it Yourself »

Convert different arrays to a number:

Number([9]);
Number([9.9]);
Number([9,9]);
Try it Yourself »

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