CSV to JSON converter

Paste CSV or TSV and get clean JSON. The delimiter and header row are detected for you, numbers and booleans can become real JSON types, and headers like address.city can become nested objects.

Delimiter

Header row

Output

Empty cells

Values Detect numbers, booleans, null Nested keys from dotted headers

CSV input

JSON output

Waiting for inputPaste CSV on the left to convert it.

How to convert CSV to JSON

Paste CSV or TSV, drop a file on the input, or click Open file. Spreadsheet exports work as they are, including quoted fields with commas or line breaks.
Check the detected delimiter and header row in the status line; override them if needed.
Copy the JSON or download it as a .json file.

Options explained

Detect numbers, booleans, null: 42 becomes a number, true a boolean and null null. Values that would be damaged stay strings: leading zeros (007), plus signs, thousands separators and integers longer than 15 digits.
Nested keys: Headers such as user.name and user.email become {"user": {"name", "email"}}, and tags.0, tags.1 become an array.
Empty cells: Keep them as empty strings, turn them into null, or leave the key out of that row.
Array of arrays: Keeps the raw grid, useful for charts or for data without a meaningful header.

Frequently asked questions

How is the delimiter detected?

The first rows are tried with commas, semicolons, tabs and pipes, and the one that splits rows into a consistent number of fields wins.

Duplicate or empty column names?

Duplicates get a suffix (name, name_2) and empty headers become column_1, column_2 and so on, so no value is overwritten.

Is there a size limit?

Only your device's memory. Files of tens of thousands of rows convert in a moment, and nothing is uploaded.