JavaScript Global Reference
Global Methods and Properties
Revised July 2025
| Name | Description |
|---|---|
| decodeURI() | Decodes a URI |
| decodeURI Component() |
Decodes a URI component |
| encodeURI() | Encodes a URI |
| encodeURI Component() |
Encodes a URI component |
| escape() | Deprecated. Use instead: encodeURI() encodeURIComponent() |
| eval() | Evaluates a string and executes it as if it was script code |
| Infinity | A numeric value that represents positive/negative infinity |
| isFinite() | Determines whether a value is a finite, legal number |
| isNaN() | Determines whether a value is an illegal number |
| NaN | "Not-a-Number" value |
| Number() | Converts an object's value to a number |
| parseFloat() | Parses a string and returns a floating point number |
| parseInt() | Parses a string and returns an integer |
| String() | Converts an object's value to a string |
| undefined | Indicates that a variable has not been assigned a value |
| unescape() | Deprecated. Use instead: decodeURI() decodeURIComponent() |
Note
Since these methods are global, and in a web browser the global object is the browser window, these methods are actually window methods:
isNaN() is the same as window.isNaN().
