---
title: Flatten json object
description: Split JSON objects in a column into individual fields.
category: Data Transformation
tags: [json, flatten, transform, parse]
---

# Flatten json object

## Description

The **Flatten Json Object** activity transforms JSON strings stored in column(s) into individual fields. It parses and expands nested properties from the selected columns, appending the new keys as new columns to the dataset.

> **Use Case**  
> Often used when JSON data is stored in a single column (e.g., API responses, logs). This activity extracts nested keys into flat columns for easier filtering, analysis, or mapping in downstream steps.

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## Input

| Type | Description                            |
| ---- | -------------------------------------- |
| Data | Dataset with one or more JSON columns. |

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## Output

| Type             | Description                                              |
| ---------------- | -------------------------------------------------------- |
| Transformed Data | Original dataset with JSON fields expanded into columns. |

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## Configuration Fields

| Field Name  | Required | Description                                                |
| ----------- | -------- | ---------------------------------------------------------- |
| **Columns** | Yes      | List of column(s) containing JSON objects to be flattened. |

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## Sample Input

| employee_id | name           | age | contact                                                       |
| ----------- | -------------- | --- | ------------------------------------------------------------- |
| E001        | John Doe       | 32  | {"email":"john.doe@example.com", "phone":"+1-555-1234"}       |
| E002        | Jane Smith     | 28  | {"email":"jane.smith@example.com", "phone":"+1-555-5678"}     |
| E003        | Ali Khan       | 40  | {"email":"ali.khan@example.com", "phone":"+1-555-9876"}       |
| E004        | Maria Gonzalez | 35  | {"email":"maria.gonzalez@example.com", "phone":"+1-555-2468"} |
| E005        | Rahul Sharma   | 30  | {"email":"rahul.sharma@example.com", "phone":"+1-555-7890"}   |

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## Sample Configuration

| Field   | Value     |
| ------- | --------- |
| Columns | `contact` |

<!-- ![alt text](flatten-json-object-img.png) -->

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## Sample Output

| employee_id | name           | age | contact                                                       | contact_email              | contact_phone |
| ----------- | -------------- | --- | ------------------------------------------------------------- | -------------------------- | ------------- |
| E001        | John Doe       | 32  | {"email":"john.doe@example.com", "phone":"+1-555-1234"}       | john.doe@example.com       | +1-555-1234   |
| E002        | Jane Smith     | 28  | {"email":"jane.smith@example.com", "phone":"+1-555-5678"}     | jane.smith@example.com     | +1-555-5678   |
| E003        | Ali Khan       | 40  | {"email":"ali.khan@example.com", "phone":"+1-555-9876"}       | ali.khan@example.com       | +1-555-9876   |
| E004        | Maria Gonzalez | 35  | {"email":"maria.gonzalez@example.com", "phone":"+1-555-2468"} | maria.gonzalez@example.com | +1-555-2468   |
| E005        | Rahul Sharma   | 30  | {"email":"rahul.sharma@example.com", "phone":"+1-555-7890"}   | rahul.sharma@example.com   | +1-555-7890   |

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> The new columns will be named based on the original column name and the JSON key (e.g., `contact_email`, `contact_phone`).