JSON ⇄ CSV Converter

Paste JSON or CSV, pick a direction, and convert. Works both ways, with no file-size limit since nothing leaves your browser.

How to use it

  1. Choose a direction: JSON → CSV or CSV → JSON.
  2. Paste your data into the input box — conversion happens as you type.
  3. Copy the result or download it as a file.

What it expects

For JSON → CSV, the input should be an array of flat(ish) objects, or an object containing one. For CSV → JSON, the first row is treated as column headers.

Frequently asked questions

Is there a file size limit?
No hard limit is enforced by this tool — since conversion happens in your browser rather than on a server, the practical limit is your own device's memory, not an artificial cap.
What happens to nested objects or arrays inside my JSON?
They're converted to a JSON string inside that CSV cell, since CSV has no native way to represent nested structure. Converting back to JSON will leave that value as a string rather than restoring the original nesting.
How does CSV → JSON decide on data types?
Values that look like numbers become numbers, "true"/"false" become booleans, and everything else stays a string. This is a best-effort guess, not a strict schema.
Does my data get uploaded anywhere?
No. The conversion happens entirely in JavaScript in your browser tab.