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---
title: Number.POSITIVE_INFINITY
slug: Web/JavaScript/Reference/Global_Objects/Number/POSITIVE_INFINITY
page-type: javascript-static-data-property
browser-compat: javascript.builtins.Number.POSITIVE_INFINITY
---
{{JSRef}}
The **`Number.POSITIVE_INFINITY`** static data property represents the positive Infinity value.
{{EmbedInteractiveExample("pages/js/number-positive-infinity.html")}}
## Value
The same as the value of the global {{jsxref("Infinity")}} property.
{{js_property_attributes(0, 0, 0)}}
## Description
The `Number.POSITIVE_INFINITY` value behaves slightly differently than mathematical infinity:
- Any positive value, including `POSITIVE_INFINITY`, multiplied by `POSITIVE_INFINITY` is `POSITIVE_INFINITY`.
- Any negative value, including {{jsxref("Number/NEGATIVE_INFINITY", "NEGATIVE_INFINITY")}}, multiplied by `POSITIVE_INFINITY` is {{jsxref("Number/NEGATIVE_INFINITY", "NEGATIVE_INFINITY")}}.
- Any positive number divided by `POSITIVE_INFINITY` is [positive zero](https://en.wikipedia.org/wiki/Signed_zero) (as defined in [IEEE 754](https://en.wikipedia.org/wiki/IEEE_754)).
- Any negative number divided by `POSITIVE_INFINITY` is [negative zero](https://en.wikipedia.org/wiki/Signed_zero) (as defined in [IEEE 754](https://en.wikipedia.org/wiki/IEEE_754).
- Zero multiplied by `POSITIVE_INFINITY` is {{jsxref("NaN")}}.
- {{jsxref("NaN")}} multiplied by `POSITIVE_INFINITY` is {{jsxref("NaN")}}.
- `POSITIVE_INFINITY`, divided by any negative value except {{jsxref("Number/NEGATIVE_INFINITY", "NEGATIVE_INFINITY")}}, is {{jsxref("Number/NEGATIVE_INFINITY", "NEGATIVE_INFINITY")}}.
- `POSITIVE_INFINITY`, divided by any positive value except `POSITIVE_INFINITY`, is `POSITIVE_INFINITY`.
- `POSITIVE_INFINITY`, divided by either {{jsxref("Number/NEGATIVE_INFINITY", "NEGATIVE_INFINITY")}} or `POSITIVE_INFINITY`, is {{jsxref("NaN")}}.
- `Number.POSITIVE_INFINITY > x` is true for any number _x_ that isn't `POSITIVE_INFINITY`.
You might use the `Number.POSITIVE_INFINITY` property to indicate an error condition that returns a finite number in case of success. Note, however, that {{jsxref("NaN")}} would be more appropriate in such a case.
Because `POSITIVE_INFINITY` is a static property of {{jsxref("Number")}}, you always use it as `Number.POSITIVE_INFINITY`, rather than as a property of a number value.
## Examples
### Using POSITIVE_INFINITY
In the following example, the variable `bigNumber` is assigned a value that is larger than the maximum value. When the {{jsxref("Statements/if...else", "if")}} statement executes, `bigNumber` has the value `Infinity`, so `bigNumber` is set to a more manageable value before continuing.
```js
let bigNumber = Number.MAX_VALUE * 2;
if (bigNumber === Number.POSITIVE_INFINITY) {
bigNumber = returnFinite();
}
```
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{jsxref("Number.NEGATIVE_INFINITY")}}
- {{jsxref("Number.isFinite()")}}
- {{jsxref("Infinity")}}
- {{jsxref("isFinite()")}}