CSV to JSON
Runs locally in your browser. Nothing leaves your device.Convert CSV, TSV files, or pasted table data to JSON directly in the browser.
CSV settings
Input
Output
Paste valid CSV data to see the JSON preview.
Paste valid CSV data to see the JSON preview.
How it works
- 1
Paste CSV or open a file
Paste CSV data or open a CSV, TSV, or TXT file.
- 2
Choose the output form and options
Choose the output form, delimiter, header row, and type detection.
- 3
Copy or download the JSON
Copy the generated JSON or download it as a file.
Good to know
The CSV to JSON converter converts CSV, TSV, or pipe data into JSON directly in your browser, with four output forms: array of objects, array of arrays, an object keyed by a chosen column, or JSON Lines. Column names with dot notation such as address.city are automatically turned into nested JSON objects.
Delimiter detection works automatically or can be set manually. A safe type-detection mode recognizes booleans, null, and safe numbers, but keeps leading zeros like 0123 and overly large integers as text to avoid precision loss. Files up to 50 MB are recommended, with a hard limit of 100 MB.
Typical use cases
Prepare an Excel export as API-ready JSON
Upload a CSV file exported from Excel to make it directly usable as an array of JSON objects for an API or application.
Group table data by a key column
Choose “object keyed by column” to generate a JSON object indexed by a unique ID column from a table.
Tips for better results
Use safe type detection for inventory numbers
Enable safe type detection when columns with leading zeros, such as postal codes or item numbers, should not accidentally become numbers.
Remove empty lines before converting
Enable “skip empty lines” when a CSV export contains stray empty lines that would otherwise end up as empty objects in the JSON.
Features
Four output forms
Array of objects, array of arrays, object keyed by column, or JSON Lines.
Safe type detection
Detects booleans, null, and safe numbers, but keeps leading zeros and overly large integers as text.
Local processing
Your file never leaves your device; conversion runs entirely in the browser.
Frequently asked questions
Are leading zeros like in postal codes preserved?
Yes, if safe type detection is active — it deliberately keeps leading zeros and overly large integers as text.
Is my file uploaded?
No. Conversion runs entirely locally in the browser.
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