CSV to JSON Converter
Turn a CSV file or pasted CSV into JSON. Your data stays on your device.
- Runs in your browser
- No sign-up
- No watermark
Paste CSV or choose a file and get a JSON list back. With a header row, each line becomes an object whose keys are the column names. Without one, each line becomes an array. Quoted values, commas and line breaks inside quotes, and Windows line endings are read correctly, and a leading byte order mark is ignored.
The conversion runs in your browser, so the file is not uploaded. A CSV with tens of thousands of rows converts in about a second.
How to use CSV to JSON
- Paste your CSV into the box, or choose or drop a file.
- Leave the delimiter on automatic, or pick comma, semicolon, tab or pipe.
- Choose whether the first row is a header and whether numbers and true/false should be converted.
- Copy the JSON or download it as a .json file.
Frequently asked questions
Is my CSV uploaded anywhere?
No. The text is parsed and converted in your browser, and nothing is sent to a server.
How does it pick the delimiter?
On automatic, it checks the first lines for comma, semicolon, tab and pipe and uses the one that gives the same number of columns on most lines. You can also choose one yourself.
Are numbers kept as numbers?
If the option is on, plain numbers become JSON numbers and true or false become booleans. Values with leading zeros, such as 007, and numbers longer than 15 digits stay text so nothing is changed or rounded. Turn the option off to keep every value as text.
What happens to empty cells and short rows?
Empty cells become empty strings. If a row has fewer values than the header, the missing keys are filled with empty strings. Extra values get names like column_5.
What if two columns have the same name?
The second one is renamed with a number, for example name and name_2, so no data is lost. Blank header names become column_1, column_2 and so on.
Does it work with a large CSV?
Yes. A file with 50,000 rows converts in about a second. For very large results the box shows only the first part, but Copy and Download include everything.