What if my CSV has no headers?

By default, the tool assumes the first row contains headers. If your CSV lacks headers, uncheck 'First row contains headers'. The converter will then generate a JSON array of arrays, or you can manually add a header row to your CSV.

Can I convert JSON back to CSV?

This tool is specifically for CSV to JSON. For the reverse operation, please check our 'JSON to CSV' tool or 'JSON to Excel' converter in the navigation menu.

CSV to JSON Converter

Free, Fast & Secure Online Tool. Instantly convert Comma Separated Values to JSON objects or arrays. Handles large files with client-side processing.

Client-Side Processing

No Uploads

Large Files Support

⚙️ Conversion Options

First row contains headers

Trim whitespace

Parse numbers & booleans

CSV Input

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JSON Output

What Is CSV?

CSV (Comma-Separated Values) is a simple text format used to store tabular data like spreasheets and databases. Each line in a CSV file corresponds to a data record, and each record consists of one or more fields separated by commas.

Common uses include:

Data Export: Moving data out of Excel, Google Sheets, or SQL databases.
Data Import: Loading contacts, products, or inventory into eCommerce platforms.
Legacy Systems: Exchanging data between older systems and modern applications.

What Is JSON?

JSON (JavaScript Object Notation) is a lightweight format for storing and transporting data. Unlike the flat structure of CSV, JSON supports hierarchical data (nested objects and arrays), making it the standard for web APIs and NoSQL databases.

Why developers convert CSV to JSON:

Web APIs: Most modern APIs accept JSON bodies, not CSV.
NoSQL Databases: MongoDB and CouchDB store data in JSON-like documents.
Data Visualization: JavaScript charting libraries (like Chart.js/D3.js) prefer JSON data sources.

CSV vs. JSON: Key Differences

Feature	CSV	JSON
Structure	Flat (Rows & Columns).	Hierarchical (Nested trees).
Readability	High (like a spreadsheet).	High (like a code block).
Data Types	Strings only (mostly).	Strings, Numbers, Booleans, Null, Objects, Arrays.
File Size	Smaller (less overhead).	Larger (repeats keys for every object).
Usage	Analysis, Reporting, Spreadsheets.	Web Apps, APIs, Configs.

How to Convert CSV to JSON Online

Paste or Upload: Paste your CSV text into the left box, or drag and drop a .csv file. We support files up to hundreds of MBs significantly faster than server-based tools.
Configure Options:
- Headers: Keep checked if row 1 contains column names.
- Parse Numbers: Check this to convert "123" to number 123.
Convert: Click the "Convert JSON" button. The tool uses your browser's processing power (via Web Workers) to prevent the page from freezing during large conversions.
Export: Copy the result to your clipboard or click the download icon to save a .json file.

Frequently Asked Questions

How to handle large CSV files?

Our tool uses Web Workers to process files on a background thread in your browser. This means the UI won't freeze even when converting files that are hundreds of megabytes in size.

Can I convert Excel to JSON?

Yes, but you first need to save your Excel file as a CSV (Comma Separated Values) file. Open your spreadsheet in Excel or Google Sheets, go to File > Save As, and select CSV format.

Is my data secure?

Yes, your data is 100% secure. We do not upload your files to any server. All conversion happens locally in your web browser using JavaScript.

Does it parse numbers and booleans?

Yes, enable the 'Parse numbers & booleans' option. The tool will detecting numeric values (123) and booleans (true) and convert them to their native JSON types.