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CSV to JSON Converter
Paste or upload any CSV and get a clean JSON array instantly – headers auto-mapped to object keys, types inferred, and the output formatted and ready to copy.
✓ Free✓ No signup✓ Privacy first✓ Runs in your browser
CSV to JSON Converter – ToolPremier

Convert CSV to JSON · auto-detect headers · handle quoted values · custom delimiters · download .json

How it works
Convert in three steps

1. Paste or upload your CSV

Drop in CSV text directly, or upload a .csv file. The first row is treated as column headers by default - toggle this if your CSV has no header row.

2. Configure the output

Choose the delimiter (comma, semicolon, tab), toggle type inference (so 42 becomes the number 42, not the string 42), and set how empty fields are handled.

3. Copy or download the JSON

Get a formatted JSON array with one object per CSV row - ready to paste into your code, feed to an API, or save as a .json file.

FAQ
Common questions
By default, the first row of the CSV is treated as the header row and becomes the key names in the JSON objects. If your CSV has no headers, disable the header row option – the converter will use column_1, column_2, etc. as key names, which you can rename manually in the output.
With type inference enabled, values that look like numbers (42, 3.14) are converted to JSON numbers rather than strings, true/false values become JSON booleans, and empty cells become null rather than empty strings. This produces a more semantically accurate JSON output that downstream code can use without type coercion. Disable it if you need all values to remain strings.
CSV values containing the delimiter character are enclosed in double quotes in standard CSV format. The converter handles quoted fields correctly and strips the enclosing quotes from the JSON output, so the value appears as the correct string in the JSON output without the extra quoting layer.
The converter processes files in your browser, so performance depends on your device. Files up to several megabytes convert quickly on modern hardware. For very large datasets (100MB+), a server-side script or dedicated data tool will be faster. For typical use cases – exported reports, API test data, spreadsheet exports – browser-side conversion is instant.
Keep going
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JSON Formatter

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Format SQL queries that insert or query the CSV data in a database.

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JSON Minifier

Compact the converted JSON for production use.

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About the CSV to JSON Converter
CSV is the lingua franca of data export – almost every database, analytics tool, and spreadsheet can produce a CSV. But modern APIs, front-end code, and data pipelines usually consume JSON. Converting a CSV export to JSON is a recurring task that is just tedious enough to disrupt a workflow. This converter handles the conversion in your browser: paste or upload the CSV, get a formatted JSON array back with proper type handling and quoting support. It covers the standard cases developers run into most – header detection, type inference, quoted fields with delimiters inside, and empty cell handling – without needing to write a parser or reach for a script.
Benefits
  • Auto-maps header row to object keys - first row detection with override option for headerless CSVs.
  • Type inference - numbers, booleans, and nulls inferred automatically, not left as strings.
  • Quoted field support - handles values containing the delimiter character without breaking the parse.
  • Client-side processing - CSV data, including personal or sensitive records, never leaves your browser.
Privacy
All conversion runs in your browser. CSV file contents are never uploaded or transmitted to any server.