100% client-side · nothing leaves your browser

JSON Editor

Edit JSON directly with live validation, find & replace, and native undo/redo — then copy or download the result.

EditorCtrl+Z / Ctrl+Y to undo/redo
Start typing or drop a .json file to edit it

How to edit JSON online

  1. Type directly, paste, or drag a .json file into the editor.
  2. Syntax is validated continuously — errors show the exact line and column.
  3. Use find & replace to update a value across the whole document at once.
  4. Copy the result or download it as a .json file when you're done.

Why use this JSON editor

Live feedback

You see the moment your edit breaks the syntax, instead of finding out later when something fails to parse.

Native undo/redo

Standard browser keyboard shortcuts just work — no need to learn a custom editor's key bindings.

Private by design

Everything happens in your browser tab. Nothing you type is saved to a server or account.

Frequently asked questions

Does this JSON editor check my syntax as I type?

Yes. The editor validates your JSON continuously and shows the exact line and column of any error as soon as you stop typing.

Can I undo changes in the online JSON editor?

Yes — the editor uses your browser's native text editing, so standard undo/redo shortcuts (Ctrl+Z / Ctrl+Y, or Cmd+Z / Cmd+Shift+Z on Mac) work as expected.

Is my edited JSON saved anywhere?

No. Editing happens entirely in your browser tab; nothing is saved to a server or account. Use the download button to save your work as a .json file.