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Data helper

CSV ⇔ JSON Converter

Convert between CSV and JSON formats seamlessly.
Support for custom delimiters (comma, tab, semicolon) and bidirectional conversion.
Perfect for data migration, spreadsheet integration, and quick data analysis.

Guide: How to use & features

  • Select the conversion direction: CSV to JSON or JSON to CSV.
  • Under "Options," specify the delimiter (comma, tab, or semicolon) for your data.
  • Paste your data into the input field to see the conversion results instantly.
  • Click "Copy Output" to grab the converted data for your project.

Samples: Sample input & output

CSV to JSON conversion

Input

id,name,role
1,Alice,Admin
2,Bob,User

Output

[
  {
    "id": "1",
    "name": "Alice",
    "role": "Admin"
  },
  {
    "id": "2",
    "name": "Bob",
    "role": "User"
  }
]

JSON to CSV conversion

Input

[
  {"id": 1, "product": "Widget", "price": 10.5},
  {"id": 2, "product": "Gadget", "price": 20.0}
]

Output

id,product,price
1,Widget,10.5
2,Gadget,20

FAQ: Frequently asked questions

  • Can I import large CSV files?

    General data up to a few megabytes works comfortably in the browser. Processing may take longer for files with extremely high row counts.

  • How is nested JSON handled when converting to CSV?

    This tool does not currently support flattening nested objects. Hierarchical data will be placed in the cell as a JSON string representation.

  • Does it support TSV (Tab-Separated Values)?

    Yes. By selecting "Tab" in the Delimiter options, you can easily convert TSV data.

Use cases: Common use cases

  • Convert Spreadsheet Data to JSON

    Convert table data copied from Excel or Google Sheets into JSON format for use as initial program data or mock APIs.

  • Export API Responses to CSV

    Convert JSON data received from an API to CSV for easier aggregation and analysis in spreadsheet software.

  • Data Format Conversion & Cleansing

    Switch between CSV and JSON while easily changing delimiters (comma/tab) to normalize your data formats.

Notes: Notes & limitations

  • Nested Structures

    When converting JSON to CSV, nested objects or arrays are not flattened. Plain, flat JSON structures are recommended.

  • Large Datasets

    Converting extremely large datasets may cause the browser to freeze or crash due to memory limitations.

CSV and JSON Converter

CSV and JSON are common data exchange formats, but they serve different workflows. This converter helps turn CSV rows into JSON objects and flatten simple JSON data into CSV for spreadsheets, tests, API fixtures, and quick data handoffs.

Common use cases

  • Create API fixtures: Convert spreadsheet exports into JSON samples for tests or mock servers.
  • Prepare spreadsheet data: Turn simple JSON records into CSV for analysis or sharing.
  • Inspect data shape: Check fields, values, and inferred types before importing data elsewhere.

Conversion note

CSV is flat, while JSON can be nested. Arrays and nested objects need a flattening or serialization convention before they can fit cleanly into columns.

Articles for this tool

Introduction
2026-05-02

CSV and JSON Conversion: Choosing the Right Format for APIs and Data Migration

Learn how to convert between CSV and JSON safely, including headers, delimiters, value types, nested data, and practical workflow tips.

Use Case
2026-05-17

Convert CSV and JSON to check data faster

A practical workflow for moving between CSV exports, API responses, and spreadsheet-style review without losing track of fields.

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