---
title: "system.util.jsonDecode"
description: "Takes a JSON string and converts it into a Python object such as a list or a dictionary."
---

# system.util.jsonDecode

> Takes a JSON string and converts it into a Python object such as a list or a dictionary.

This function is used in **Python Scripting**.

## Description
Takes a JSON string and converts it into a Python object such as a list or a dictionary. If the input is not valid JSON, a string is returned.

## Client Permission Restrictions
This scripting function has no [Client Permission](../../../ignition-modules/vision/vision-project-properties/vision-project-properties.md#vision-permissions-properties) restrictions.

## Syntax
`system.util.jsonDecode(jsonString)`

### Parameters
Type | Parameter | Description 
------- | ------- | ------
String| `jsonString` | The JSON string to decode into a Python object.

### Returns
**Any** - The decoded Python object. See the table below for a listing of how JSON objects are mapped to Python objects. 

### Scope
Gateway, Vision Client, Perspective Session

## JSON to Python Mapping
The table below lists possible JSON types, and the Python types this function maps to. 

|JSON Type|Mapped Python Type|
|--|--|
|Boolean (true/false)	|Boolean (True/False)|
|String	|String|
|Numeric	|Number (Float, Integer)|
|null	|None|
|Array	|List|
|Object|	Dictionary|

## Code Examples
```python title="Example #1"
# The following example reads in a JSON string, and converts the string to a Python object.
# The example attempts to read the JSON string from a text file, but this could easily be modified to read data from a web server.
  
# Read the JSON string
jsonString = system.file.readFileAsString("C:\tmp\\json.txt")
  
# Decode the JSON string and store the results into a variable
obj = system.util.jsonDecode(jsonString)
  
# Do something with the results. The code below prints the datatype of the results to the console.
print type(obj)
```