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CSV to JSON

Convert CSV data into clean, structured JSON instantly in your browser — with delimiter auto-detection, quoted and multiline field support, header handling and conservative type detection.

Paste CSV, load a file, or drag & drop one here.

Options

Duplicate or empty column names are renamed automatically (name, name_2, column_3...). Extra columns are kept under extra_1, extra_2 keys unless Strict rows is on. Type detection is conservative: leading zeros, long numbers and dates stay strings.

Your CSV is converted locally in your browser and is never uploaded.

How it works

  1. 1Paste your CSV. Type or paste CSV data, or load a local .csv or .txt file — it is parsed entirely in your browser.
  2. 2Choose conversion options. Set the delimiter (auto-detect, comma, semicolon, tab, pipe or custom), toggle the header row, trim whitespace, skip empty rows, and choose how empty values are handled.
  3. 3Convert to JSON. Click Convert to JSON. Quoted commas, escaped quotes and multiline fields are handled correctly by the CSV parser.
  4. 4Copy or download. Copy the JSON, download it as a UTF-8 .json file, or load the sample data to try the tool. Tamil, Hindi and emoji are preserved exactly.

Best practices

  • Use the header row option when your first CSV line contains column names — they become the JSON object keys.
  • Quoted fields are respected: commas, quotes (escaped as ""), and newlines inside quotes stay inside a single value.
  • Keep type detection off unless you know the data: phone numbers, ZIP codes and IDs with leading zeros are always kept as strings.
  • Use Strict Rows to catch uneven rows instead of silently padding or renaming extra columns.

Frequently Asked Questions

What does CSV to JSON do?
It parses CSV text or a local .csv/.txt file and converts it into structured JSON — an array of objects (default), an array of arrays, or an object keyed by row number.
Does the first CSV row become JSON keys?
Yes. With the header row option on (the default), the first row is used as the column names and every record becomes a JSON object. Turn it off to get an array of arrays instead.
Can CSV values contain commas?
Yes. Values wrapped in double quotes may contain commas, escaped quotes (""), and even line breaks, and they stay inside a single JSON value.
Does it support quoted and multiline fields?
Yes. The built-in RFC-style parser handles quoted commas, doubled quote escaping, and fields that span multiple lines, so "Line one + Line two" stays one value.
Can I choose semicolon or tab delimiter?
Yes. The delimiter can be auto-detected (comma, semicolon, tab or pipe) or chosen manually, including a custom 1-3 character delimiter.
Can it detect numbers and booleans?
Yes, when type detection is on — obvious booleans, null, integers and decimals become JSON values. Leading-zero codes, phone numbers, IDs and unsafe integers are always kept as strings.
Can I upload a CSV file?
Yes. You can load a local .csv or .txt file (up to 5 MB) with the file picker. The file is read locally in your browser and never uploaded anywhere.
Does it support Tamil/Unicode?
Yes. Tamil, Hindi, Arabic, CJK, emoji and mixed-language data are preserved exactly, including UTF-8 BOM handling for exported CSV files.
Is my CSV uploaded?
No. The conversion runs entirely in your browser. Your text and files never leave your device.

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Supported data

Convert CSV text or local .csv/.txt files (up to 5 MB) with comma, semicolon, tab or pipe delimiters. RFC-style quoting with escaped quotes and multiline fields is supported, along with Unicode content — English, Tamil, Hindi, Arabic, CJK and emoji — and UTF-8 BOM handling. Everything is parsed directly in your browser.

Privacy & data removal

Your CSV is converted entirely in your browser. Nothing — text or files — is uploaded to any server. No account is required to use CSV to JSON, and we never store or share your data.