CSV to JSON converter

Paste CSV, or load a file, and get clean JSON: one object per row, keys from the header, numbers and booleans converted. Comma, semicolon or tab, all detected. Nothing is uploaded.

  • Free
  • No sign-up
  • Runs in your browser
csv-to-json

100% private — your text is processed in your browser and never sent to any server.

Next step

Keep going with your result in another tool. Nothing is uploaded.

How it works

Paste or load your CSV

Paste the text or use the file box. The first row is treated as the header by default.

Set the options

Pick the separator, or let the tool detect it, and choose the JSON indentation.

Copy or download the JSON

The result appears as you type; copy it or download a .json file.

How to convert CSV to JSON

To convert CSV to JSON, paste your CSV in the input box with CSV to JSON selected. The first row becomes the keys, every other row becomes an object, and the whole thing is an array you can copy or download. Numbers, true, false and null are turned into real JSON values, and quoted fields with commas inside are kept intact. It all happens in your browser.

A worked example

This CSV, with a quoted field that contains a comma and an empty cell:

Input

name,age,city
Ana,31,Madrid
Ben,28,"Austin, TX"
Cleo,,Paris

Output

[
  {
    "name": "Ana",
    "age": 31,
    "city": "Madrid"
  },
  {
    "name": "Ben",
    "age": 28,
    "city": "Austin, TX"
  },
  {
    "name": "Cleo",
    "age": "",
    "city": "Paris"
  }
]

Details that trip people up

  • Separators. Files exported by Excel in many countries use a semicolon, because the comma is the decimal separator there. Choose the separator or let the tool detect it.
  • Quotes. A field wrapped in double quotes may contain commas and line breaks. A double quote inside it is written as two.
  • Types. Numbers, true, false and null become JSON values; untick the option to keep everything as text, which is safer for IDs such as 00123.
  • Empty cells. Choose whether they become empty strings or null.

Why convert CSV to JSON

CSV is the format of spreadsheets and exports, and JSON is the format of APIs and code. Converting lets you load spreadsheet data into a web app, seed a database, mock an API response or feed a chart library. The reverse, JSON to CSV, is handled by the same tool.

Private by design

The conversion runs in your browser. What you type, paste or drop is never uploaded, which matters when the text holds tokens, personal data or internal files.

More developer and text tools

Frequently asked questions

Does the CSV need a header row?
By default the first row is the header and provides the JSON keys. Untick the header option and every row becomes an array of values instead.
Why are my numbers strings in the JSON?
Numbers become real JSON numbers when the type conversion option is on. Turn it off to keep values such as ZIP codes and IDs with leading zeros as text.
Can it handle large files?
It handles files of several megabytes, limited by your device's memory since everything runs in the browser. For very large exports, split the file first.
Is this converter free?
Yes. There is no sign-up and no limit, and it runs in your browser, so nothing you type is sent to a server.
Does it work on a phone?
Yes. It works in any modern mobile browser, and the result updates as you type.

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