Number validation

README.md

@@ -26,6 +26,7 @@
 * [Unique values of array](#unique-values-of-array)
 * [URL parameters](#url-parameters)
 * [UUID generator](#uuid-generator)
+* [Validate number](#validate-number)
 
 ### Anagrams of string (with duplicates)
 
@@ -209,6 +210,15 @@ var uuid = _ =>
   )
 ```
 
+### Validate number
+
+Use `!isNaN` in combination with `parseFloat()` to check if the argument is a number.
+Use `isFinite()` to check if the number is finite.
+
+```js
+var validateNumber = n => !isNaN(parseFloat(n)) && isFinite(n);
+```
+
 ## Credits
 
 *Icons made by [Smashicons](https://www.flaticon.com/authors/smashicons) from [www.flaticon.com](https://www.flaticon.com/) is licensed by [CC 3.0 BY](http://creativecommons.org/licenses/by/3.0/).*

snippets/validate-number.md

@@ -0,0 +1,8 @@
+### Validate number
+
+Use `!isNaN` in combination with `parseFloat()` to check if the argument is a number.
+Use `isFinite()` to check if the number is finite.
+
+```js
+var validateNumber = n => !isNaN(parseFloat(n)) && isFinite(n);
+```