Local data converter
CSV to JSON Converter
Paste or upload delimited data, confirm the structure, and download a clean JSON array.
01 / Input
Add CSV data
Or drag and drop a file onto this field.
Choose one delimited text file up to 5 MB. It stays on this device.
Quoted delimiters, escaped quotes, and line breaks inside quoted fields are supported.
02 / Configure
Set delimiter and headers
Auto detect checks comma, tab, semicolon, and pipe separators.
JSON keys
Add valid CSV data to configure its JSON keys.
03 / Preview
Check parsed rows
No rows parsed
Parsed rows will appear here before you download JSON.
CSV parsing and JSON downloads require JavaScript in this browser.
How it works
Convert CSV to JSON in three steps
Use a local file or pasted text. The converter checks the structure before it creates an array of JSON objects.
- 01 Add your CSV data.
Upload a CSV, TSV, or text file up to 5 MB, or paste data into the editor.
- 02 Check the delimiter and headers.
Keep automatic delimiter detection or select comma, tab, semicolon, or pipe. Use the first row as headers or edit generated JSON keys.
- 03 Preview and download.
Review the first parsed rows, then save every row in one formatted JSON file.
01 / Privacy
Keep CSV data on your device
Files and pasted text are parsed in your browser. Nanomite does not upload, store, or add the data to the page URL.
02 / CSV support
Handle quoted CSV fields
The parser supports escaped quotes, delimiters inside quoted fields, Windows or Unix line endings, and line breaks inside quoted values.
03 / JSON output
Preserve values as text
Each data row becomes a JSON object. Values stay as strings, missing cells become empty strings, and no dates, numbers, or booleans are guessed.