CSV to JSON Converter Free Online

Free online CSV to JSON converter. Paste CSV data and instantly convert it to a JSON array. Download the result.

JSON output...

Input format

First row must be headers. Each subsequent row becomes a JSON object with header names as keys.

CSV files from spreadsheets, databases, and data exports need to be converted to JSON for use in web APIs, JavaScript applications, Node.js scripts, and NoSQL databases. Whether you are taking a Google Sheets export and loading it into a web app, converting a database dump for API testing, or transforming a data export for use in a JavaScript project - this free CSV to JSON converter handles the transformation instantly in your browser without any server upload.

How to Use the CSV to JSON Converter

1

Paste or upload your CSV

Paste CSV data directly into the input field, or click Upload to select a .csv file from your device. The converter accepts standard comma-delimited CSV, semicolon-delimited CSV (common in European locales), and tab-separated values (TSV). The delimiter is auto-detected from your data.

2

Click Convert to JSON

Click the Convert button. The first row of your CSV is used as the JSON property names (keys) for each record. Each subsequent row becomes a JSON object with those properties. The result is a JSON array where each element is an object representing one CSV row, which is the standard format expected by most web APIs and JavaScript data processing functions.

3

Copy or download the JSON

Click Copy to copy the JSON output to your clipboard for immediate use in code, API testing tools like Postman, or configuration files. Click Download to save the JSON as a .json file for use in projects, scripts, or data pipelines.

Why Convert CSV to JSON?

Loading spreadsheet data into web applications - many data sources are maintained in spreadsheets (Google Sheets, Excel). Converting them to JSON allows the data to be imported into web application databases, configuration systems, or JavaScript code as structured objects rather than as raw text strings.

API testing and development - when building or testing REST APIs, you often need sample data in JSON format. If your sample data is in a spreadsheet, converting it to JSON array format lets you use it directly in API testing tools like Postman, Insomnia, or as mock data in development environments.

NoSQL database seeding - MongoDB, DynamoDB, Firestore, and other document databases accept JSON for data import. Converting CSV data to JSON array format provides a ready-to-import dataset for database seeding and testing.

JavaScript and Node.js data processing - many data processing scripts work with JSON arrays natively. Converting a CSV file to a JSON array lets you load the data directly into JavaScript arrays and objects for processing with .map(), .filter(), and .reduce().

Frequently Asked Questions

Does it use the first row as column headers?
Yes. The first row of your CSV is treated as the header row and its values become the property names (keys) in the JSON objects. Each subsequent row becomes a JSON object with those properties as keys and the corresponding cell values as values. Make sure your CSV has a properly formatted header row before converting.
What CSV delimiters are supported?
The converter auto-detects and supports comma (,), semicolon (;), and tab (\t) delimiters. Semicolons are commonly used in European locale CSV files where commas are used as decimal separators. Tab-separated values (TSV files) exported from some applications are also supported. Quoted fields containing the delimiter character are correctly handled - a comma inside a double-quoted field is treated as data, not as a delimiter.
Can I upload a CSV file directly?
Yes. Click the Upload button to select a .csv file from your device. The file is read locally in your browser - it is never uploaded to any server. You can also paste CSV text directly into the input field if you prefer not to use file upload.
How are numbers and booleans handled?
The converter auto-detects numeric and boolean values in CSV cells. Cells containing only digits (with or without a decimal point) are converted to JSON numbers rather than strings. Cells containing "true" or "false" (case-insensitive) are converted to JSON boolean values. All other cells are converted to JSON strings. This produces more semantically correct JSON that matches typical API response formats.
Is my CSV data sent to a server?
No. All conversion happens entirely in your browser using JavaScript. Neither pasted CSV text nor uploaded CSV files are ever transmitted to any server. Everything is processed locally in your browser memory. This makes the tool safe for converting sensitive data like customer lists, financial records, or any confidential business data.