CSV to JSON Converter Online

Turn CSV tables into JSON objects and arrays without uploading your data or installing any software.

Browser-based conversion with a simple import flow.

CSV input 0 B

Drop a file here or choose one below

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JSON output 0 B

Delimiter First row is header Auto-convert types Trim whitespace Skip empty lines Unflatten dot paths Output mode Key column Indentation

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Input: 0 KB Output: 0 KB Lines: 0 Time: 0 ms

How to convert CSV to JSON

Open the converter, paste CSV text into the input panel, or upload a .csv file from your device. The tool detects the most likely delimiter, trims whitespace, and optionally removes empty lines so your table lands in a clean and consistent structure. If the first row contains headings, the converter uses those as keys and creates a JSON array of objects. If there is no header row, you can select the array-of-arrays mode to keep the raw structure intact.

For modern APIs and JavaScript apps, auto-convert types is essential. When enabled, strings such as 42, true, false, and null become real JSON values instead of strings, making the output easier to consume in code. If your CSV was originally exported from a flat spreadsheet, you can also unflatten dotted keys back into nested objects and convert repeated fields such as profile.name or settings.theme into a structured object.

The output is previewed immediately and can be copied or downloaded as a .json file. This is especially helpful when migrating legacy exports, reading dashboard exports, or turning spreadsheet content into structured data for a front-end app or back-end endpoint.

Before and after example

Think of a product export from a spreadsheet with columns such as name, price, in_stock, and categories. The CSV rows are easy to edit in Excel and Google Sheets, but your application needs structured JSON. The converter turns each row into an object and makes the output ready for fetch calls, front-end rendering, or data-processing pipelines. For a CSV with a first row of headers, the output becomes a clean array of objects with each field mapped to a property name.

Common use cases

Data teams often receive CSV exports from CRMs, ERP systems, or SaaS tools and need to convert them into JSON for API testing or local development. Front-end developers use this conversion to seed sample data, validate import pipelines, and map spreadsheet columns into app state. Product teams also use it to move static records from a spreadsheet into configuration files or database import scripts.

Because the tool is browser-based, it is useful for confidential data such as customer lists, inventory exports, or internal reporting. You can run the conversion locally with no backend, no credentials, and no data leaving the page.

Things to watch out for

The biggest risk in CSV-to-JSON conversion is type ambiguity. A value like 001 may be read as the number 1, while a spreadsheet cell exported as a date or time string may need additional formatting. If your CSV contains commas or newlines inside a field, quoting and delimiter detection matter. Use the delimiter and trim options to reduce surprises, and review the JSON output before using it in scripts or saved config files.

Frequently asked questions

Can this detect the CSV delimiter automatically?

Yes. The converter tries common separators such as comma, semicolon, tab, and pipe and picks the most likely match for your file.

Does it preserve numbers and booleans?

Yes. With auto-convert enabled, values such as 42, true, and null are converted to real JSON data types rather than plain strings.

What if my CSV has no header row?

You can turn off the header option and receive an array of arrays instead of an array of objects.

Can I turn dot-notated names back into nested objects?

Yes. Use the unflatten option when your CSV columns include names like user.address.city or profile.name.

Is it safe for sensitive data?

Yes. The file is read and transformed locally in your browser and is never sent to a remote server.