JSON Visual Form & Tree Editor

Editing large JSON files in a text editor is error-prone: one missing comma or bracket breaks the whole document, and deeply nested data is hard to navigate. A tree editor shows the structure as expandable nodes, lets you edit values directly and validates as you go. This editor combines a tree view, a form-style view and a text view.

How to use it

1. Paste JSON or start with an empty document.
2. Expand and collapse nodes to navigate nested objects and arrays.
3. Edit values, rename keys, add or remove items and change types.
4. Switch to the text view to see and copy the formatted result.

When a tree editor helps

• Large API responses: collapse everything and drill into the part you care about.
• Config files: change a value deep inside nested settings without breaking syntax.
• Test data: build fixtures by adding and duplicating items.
• Non-developers: people who are not comfortable with brackets and commas can still edit structured data safely.

Live error checking

In text mode, syntax errors are reported with their position. The most common mistakes are:

• Trailing commas after the last item, which JSON does not allow.
• Single quotes instead of double quotes around strings and keys.
• Unquoted keys, valid in JavaScript but not in JSON.
• Comments, which standard JSON does not support.

Types matter

A value of 42 is a number, but '42' (in double quotes in real JSON) is a string. APIs often reject the wrong type, so check types when editing values.

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