How to edit JSON online
- Paste JSON, open a file or start with the sample. The tree is built from the text automatically.
- Double-click a value or key in the tree to edit it and press Enter to save. Select a node to Add a child, Duplicate or Delete it, or change its Type.
- Every change in the tree rewrites the text, and Undo steps back. Copy or download the result when you are done.
Editing in the tree
- Values – when you edit a string it stays a string. For other values, what you type is read as JSON:
42becomes a number,truea boolean,nullnull and anything else a string. - Keys – double-click a key to rename it; the property keeps its position.
- Add – on an object it adds
"newKey": null, on an array it appendsnull, and on a single value it inserts a new item after it. - Type – converts between string, number, boolean, null, object and array, for example
"42"→42or a value →[value]. - Keyboard – arrow keys move through the tree, Enter or F2 edits the selected value and Delete removes the node.
Text and tree stay in sync
Changes in the text pane update the tree as soon as the JSON is valid; while it is invalid, the error box shows the problem and the tree keeps the last valid version. Changes in the tree rewrite the text with 2-space indentation, keeping the order of keys and the exact digits of every number. Undo remembers the last 100 tree changes.
Frequently asked questions
Does the editor change key order or numbers?
No. Keys stay in their original order and numbers keep their exact digits, including 64-bit IDs that ordinary JavaScript would round.
How do I add a new property?
Select the object in the tree and click Add. A property called newKey with the value null appears; double-click it to rename it and set its value.
Which file sizes work well?
The editor is made for documents up to a few megabytes. To browse much larger files, use the JSON Viewer, which only draws the parts you expand.
Are my edits saved anywhere?
Nothing is stored or uploaded. Copy the text or click Download to keep your changes.