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# is-number [](http://badge.fury.io/js/is-number) [](https://travis-ci.org/jonschlinkert/is-number)
> Returns true if the value is a number. comprehensive tests.
To understand some of the rationale behind the decisions made in this library (and to learn about some oddities of number evaluation in JavaScript), [see this gist](https://gist.github.com/jonschlinkert/e30c70c713da325d0e81).
## Install
Install with [npm](https://www.npmjs.com/)
```sh
$ npm i is-number --save
```
## Usage
```js
var isNumber = require('is-number');
```
### true
See the [tests](./test.js) for more examples.
```js
isNumber(5e3) //=> 'true'
isNumber(0xff) //=> 'true'
isNumber(-1.1) //=> 'true'
isNumber(0) //=> 'true'
isNumber(1) //=> 'true'
isNumber(1.1) //=> 'true'
isNumber(10) //=> 'true'
isNumber(10.10) //=> 'true'
isNumber(100) //=> 'true'
isNumber('-1.1') //=> 'true'
isNumber('0') //=> 'true'
isNumber('012') //=> 'true'
isNumber('0xff') //=> 'true'
isNumber('1') //=> 'true'
isNumber('1.1') //=> 'true'
isNumber('10') //=> 'true'
isNumber('10.10') //=> 'true'
isNumber('100') //=> 'true'
isNumber('5e3') //=> 'true'
isNumber(parseInt('012')) //=> 'true'
isNumber(parseFloat('012')) //=> 'true'
```
### False
See the [tests](./test.js) for more examples.
```js
isNumber('foo') //=> 'false'
isNumber([1]) //=> 'false'
isNumber([]) //=> 'false'
isNumber(function () {}) //=> 'false'
isNumber(Infinity) //=> 'false'
isNumber(NaN) //=> 'false'
isNumber(new Array('abc')) //=> 'false'
isNumber(new Array(2)) //=> 'false'
isNumber(new Buffer('abc')) //=> 'false'
isNumber(null) //=> 'false'
isNumber(undefined) //=> 'false'
isNumber({abc: 'abc'}) //=> 'false'
```
## Other projects
* [even](https://www.npmjs.com/package/even): Get the even numbered items from an array. | [homepage](https://github.com/jonschlinkert/even)
* [is-even](https://www.npmjs.com/package/is-even): Return true if the given number is even. | [homepage](https://github.com/jonschlinkert/is-even)
* [is-odd](https://www.npmjs.com/package/is-odd): Returns true if the given number is odd. | [homepage](https://github.com/jonschlinkert/is-odd)
* [is-primitive](https://www.npmjs.com/package/is-primitive): Returns `true` if the value is a primitive. | [homepage](https://github.com/jonschlinkert/is-primitive)
* [kind-of](https://www.npmjs.com/package/kind-of): Get the native type of a value. | [homepage](https://github.com/jonschlinkert/kind-of)
* [odd](https://www.npmjs.com/package/odd): Get the odd numbered items from an array. | [homepage](https://github.com/jonschlinkert/odd)
## Contributing
Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](https://github.com/jonschlinkert/is-number/issues/new).
## Run tests
Install dev dependencies:
```sh
$ npm i -d && npm test
```
## Author
**Jon Schlinkert**
+ [github/jonschlinkert](https://github.com/jonschlinkert)
+ [twitter/jonschlinkert](http://twitter.com/jonschlinkert)
## License
Copyright © 2015 Jon Schlinkert
Released under the MIT license.
***
_This file was generated by [verb-cli](https://github.com/assemble/verb-cli) on November 22, 2015._