Free CSV to JSON Converter
Convert CSV files or spreadsheet text into structured JSON arrays and objects. Features custom delimiters, auto number parsing, nested JSON evaluation, matrix transpose, and live data table preview.
CSV Input
JSON Output
CSV Data Table Preview
0 Records| # | No Data Loaded |
|---|---|
| Paste CSV input or upload CSV files above to view formatted spreadsheet preview. | |
About the Free CSV to JSON Converter Tool
This tool allows you to convert CSV and spreadsheet text into organized JSON data with ease. This tool is completely private, and your files and data never leave your device. It is 100% free to use, requires no signup or login, and offers unlimited use.
How to Convert CSV to JSON in 4 Easy Steps
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Paste your CSV or TSV text into the input panel or upload a
.csvfile. -
Choose your delimiter (Comma, Tab, Semicolon, Pipe) and output format (Array of Objects, 2D Array, Key-Value Object).
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Toggle auto-type conversion for numbers and booleans or unnest dot-notation headers.
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Click Download JSON to save your file or click Copy to copy the output string to your clipboard.
Features & How It Works
100% Free & Private
All CSV parsing and JSON generation run directly on your device. This tool is completely private, and your files and data never leave your device.
Flexible Output Structures
Choose how your records are formatted, including standard lists of items, clean two-dimensional table grids, or keyed groupings indexed by your unique IDs.
Nested Hierarchy Support
Easily converts dot-notation column headers (such as contact.address.city) into organized, structured nested JSON records.
Flexible Delimiters
Supports standard CSV commas, tabs (TSV), semicolons, and custom separator characters for maximum spreadsheet compatibility.
Live Data Table Preview
Inspect your parsed spreadsheet records in an interactive table view before saving, ensuring full visual accuracy.
Multi-File Batch Conversion
Convert multiple CSV documents simultaneously and download all JSON results individually or in a single ZIP file.
Frequently Asked Questions
Can this tool convert TSV or semicolon-separated files?
Yes! You can choose automatic delimiter detection or manually select Comma (,), Tab (\t), Semicolon (;), or Pipe (|) delimiters.
How does nested object unflattening work?
When enabled, column names containing dots (e.g. contact.email) are transformed into nested JSON objects like {"contact": {"email": "val"}}.
Are my uploaded CSV files stored on your server?
No. This tool is completely private, and your files and data never leave your device. All parsing runs locally on your machine with zero server uploads.
Is this CSV to JSON converter 100% free to use?
Yes! The tool is 100% free with no login, signup, or subscription required. You can convert unlimited CSV documents with unlimited rows.
Can I convert multiple CSV files at once?
Yes! Select multiple .csv files at once. The converter processes each file into structured JSON output and allows you to download them individually or as a single batch ZIP file.
Is there a row or file size limit for CSV conversion?
No, there are no set limits on file size or row counts. You can convert spreadsheets with tens of thousands of rows with unlimited free use. Because conversion runs locally on your device, capacity is only limited by your device's available memory.
Can I export formatted JSON with indentation or compact JSON?
Yes! You can choose between beautified 2-space or 4-space indented JSON for easy reading, or compact minified JSON for minimal file size.