# Number

`Number` is a primitive wrapper object used to represent and manipulate numbers like `37` or `-9.25`.

The `Number` constructor contains constants and methods for working with numbers. Values of other types can be converted to numbers using the `Number()` function.

The JavaScript Number type is a double-precision 64-bit binary format IEEE 754 value, like `double` in Java or C#. This means it can represent fractional values, but there are some limits to what it can store. A Number only keeps about 17 decimal places of precision; arithmetic is subject to rounding. The largest value a Number can hold is about 1.8×10308. Numbers beyond that are replaced with the special Number constant `Infinity`.

A number literal like `37` in JavaScript code is a floating-point value, not an integer. There is no separate integer type in common everyday use. (JavaScript now has a `BigInt` type, but it was not designed to replace Number for everyday uses. `37` is still a Number, not a BigInt.)

Number may also be expressed in literal forms like `0b101`, `0o13`, `0x0A`. Learn more on numeric lexical grammar here.

## Description

When used as a function, `Number(value)` converts a string or other value to the Number type. If the value can't be converted, it returns `NaN`.

### Literal syntax

```123    // one-hundred twenty-three
123.0  // same
123 === 123.0  // true```

### Function syntax

```Number('123')  // returns the number 123
Number('123') === 123  // true

Number("unicorn")  // NaN
Number(undefined)  // NaN
```

## Constructor

`Number()`
Creates a new `Number` value.

## Static properties

`Number.EPSILON`
The smallest interval between two representable numbers.
`Number.MAX_SAFE_INTEGER`
The maximum safe integer in JavaScript (`253 - 1`).
`Number.MAX_VALUE`
The largest positive representable number.
`Number.MIN_SAFE_INTEGER`
The minimum safe integer in JavaScript (`-(253 - 1)`).
`Number.MIN_VALUE`
The smallest positive representable number—that is, the positive number closest to zero (without actually being zero).
`Number.NaN`
Special "Not a Number" value.
`Number.NEGATIVE_INFINITY`
Special value representing negative infinity. Returned on overflow.
`Number.POSITIVE_INFINITY`
Special value representing infinity. Returned on overflow.
`Number.prototype`
Allows the addition of properties to the `Number` object.

## Static methods

`Number.isNaN()`
Determine whether the passed value is `NaN`.
`Number.isFinite()`
Determine whether the passed value is a finite number.
`Number.isInteger()`
Determine whether the passed value is an integer.
`Number.isSafeInteger()`
Determine whether the passed value is a safe integer (number between `-(253 - 1)` and `253 - 1`).
`Number.parseFloat(string)`
This is the same as the global `parseFloat()` function.
`Number.parseInt(string, [radix])`
This is the same as the global `parseInt()` function.

## Instance methods

`Number.prototype.toExponential(fractionDigits)`
Returns a string representing the number in exponential notation.
`Number.prototype.toFixed(digits)`
Returns a string representing the number in fixed-point notation.
`Number.prototype.toLocaleString([locales [, options]])`
Returns a string with a language sensitive representation of this number. Overrides the `Object.prototype.toLocaleString()` method.
`Number.prototype.toPrecision(precision)`
Returns a string representing the number to a specified precision in fixed-point or exponential notation.
`Number.prototype.toString([radix])`
Returns a string representing the specified object in the specified radix ("base"). Overrides the `Object.prototype.toString()` method.
`Number.prototype.valueOf()`
Returns the primitive value of the specified object. Overrides the `Object.prototype.valueOf()` method.

## Examples

### Using the Number object to assign values to numeric variables

The following example uses the `Number` object's properties to assign values to several numeric variables:

```const biggestNum     = Number.MAX_VALUE
const smallestNum    = Number.MIN_VALUE
const infiniteNum    = Number.POSITIVE_INFINITY
const negInfiniteNum = Number.NEGATIVE_INFINITY
const notANum        = Number.NaN
```

### Integer range for Number

The following example shows the minimum and maximum integer values that can be represented as `Number` object. (More details on this are described in the ECMAScript standard, chapter 6.1.6 The Number Type.)

```const biggestInt  = Number.MAX_SAFE_INTEGER  //  (`253 - 1`) =>  9007199254740991
const smallestInt = Number.MIN_SAFE_INTEGER  // -(`253 - 1`) => -9007199254740991```

When parsing data that has been serialized to JSON, integer values falling outside of this range can be expected to become corrupted when JSON parser coerces them to `Number` type.

A possible workaround is to use `String` instead.

Larger numbers can be represented using the `BigInt` type.

### Using Number to convert a Date object

The following example converts the `Date` object to a numerical value using `Number` as a function:

```let d = new Date('December 17, 1995 03:24:00')
console.log(Number(d))
```

This logs `819199440000`.

### Convert numeric strings and null to numbers

```Number('123')     // 123
Number('123') === 123 /// true
Number('12.3')    // 12.3
Number('12.00')   // 12
Number('123e-1')  // 12.3
Number('')        // 0
Number(null)      // 0
Number('0x11')    // 17
Number('0b11')    // 3
Number('0o11')    // 9
Number('foo')     // NaN
Number('100a')    // NaN
Number('-Infinity') //-Infinity```

## Browser compatibility

Update compatibility data on GitHub
Desktop Mobile Server Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 3 Opera Full support 3 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 34 Edge Full support 12 Firefox Full support 25 IE No support No Opera Full support 21 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 34 Firefox Android Full support 25 Opera Android Full support 21 Safari iOS Full support 9 Samsung Internet Android Full support 2.0 nodejs Full support 0.12 Chrome Full support 34 Edge Full support 12 Firefox Full support 31 IE No support No Opera Full support 21 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 34 Firefox Android Full support 31 Opera Android Full support 21 Safari iOS Full support 9 Samsung Internet Android Full support 2.0 nodejs Full support 0.12 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 4 Opera Full support 3 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 34 Edge Full support 12 Firefox Full support 31 IE No support No Opera Full support 21 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 34 Firefox Android Full support 31 Opera Android Full support 21 Safari iOS Full support 9 Samsung Internet Android Full support 2.0 nodejs Full support 0.12 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 4 Opera Full support 3 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 4 Opera Full support 3 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 4 Opera Full support 3 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 3 Opera Full support 3 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 4 Opera Full support 3 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 19 Edge Full support 12 Firefox Full support 16 IE No support No Opera Full support 15 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 25 Firefox Android Full support 16 Opera Android Full support 14 Safari iOS Full support 9 Samsung Internet Android Full support 1.5 nodejs Full support 0.10 Chrome Full support 34 Edge Full support 12 Firefox Full support 16 IE No support No Opera Full support 21 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 34 Firefox Android Full support 16 Opera Android Full support 21 Safari iOS Full support 9 Samsung Internet Android Full support 2.0 nodejs Full support 0.12 Chrome Full support 25 Edge Full support 12 Firefox Full support 15 IE No support No Opera Full support 15 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 25 Firefox Android Full support 15 Opera Android Full support 14 Safari iOS Full support 9 Samsung Internet Android Full support 1.5 nodejs Full support 0.10 Chrome Full support 34 Edge Full support 12 Firefox Full support 32 IE No support No Opera Full support 21 Safari Full support 10 WebView Android Full support ≤37 Chrome Android Full support 34 Firefox Android Full support 32 Opera Android Full support 21 Safari iOS Full support 10 Samsung Internet Android Full support 2.0 nodejs Full support 0.12 Chrome Full support 34 Edge Full support 12 Firefox Full support 25 IE No support No Opera Full support 21 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 34 Firefox Android Full support 25 Opera Android Full support 21 Safari iOS Full support 9 Samsung Internet Android Full support 2.0 nodejs Full support 0.12 Chrome Full support 34 Edge Full support 12 Firefox Full support 25 IE No support No Opera Full support 21 Safari Full support 9 WebView Android Full support ≤37 Chrome Android Full support 34 Firefox Android Full support 25 Opera Android Full support 21 Safari iOS Full support 9 Samsung Internet Android Full support 2.0 nodejs Full support 0.12 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 5.5 Opera Full support 7 Safari Full support 2 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 5.5 Opera Full support 7 Safari Full support 2 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12Notes Full support 12Notes Notes Before Edge 18, numbers are rounded to 15 decimal digits. For example, `(1000000000000005).toLocaleString('en-US')` returns `"1,000,000,000,000,010"`. Firefox Full support 1 IE Full support 5Notes Full support 5Notes Notes In Internet Explorer 11, numbers are rounded to 15 decimal digits. For example, `(1000000000000005).toLocaleString('en-US')` returns `"1,000,000,000,000,010"`. Opera Full support 4 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 5.5 Opera Full support 7 Safari Full support 2 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome No support No Edge No support No Firefox No support 1 — 74Notes No support 1 — 74Notes Notes Starting in Firefox 74, `toSource()` is no longer available for use by web content. It is still allowed for internal and privileged code. IE No support No Opera No support No Safari No support No WebView Android No support No Chrome Android No support No Firefox Android Full support 4 Opera Android No support No Safari iOS No support No Samsung Internet Android No support No nodejs No support No Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 3 Opera Full support 4 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100 Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 4 Opera Full support 4 Safari Full support 1 WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support 10.1 Safari iOS Full support 1 Samsung Internet Android Full support 1.0 nodejs Full support 0.1.100

### Legend

Full support
Full support
No support
No support
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.
See implementation notes.
See implementation notes.