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JSON Editor

Edit JSON with syntax highlighting and live validation. Update an API payload, adjust a configuration, or draft test data, then format and copy your changes.

JSON source editor

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Edit JSON payloads with immediate syntax feedback

Use the code editor to change property names, values, and array items while checking whether the document still parses. The workspace keeps invalid intermediate text while you work. Formatting is an explicit action, so typing does not continually rearrange your document. Copy the finished text back into your application when you are ready.

How to use the JSON Editor

  1. Paste a configuration or start writing JSON in the editor.
  2. Change the source and use the validation panel to catch syntax mistakes.
  3. Choose Format Changes if needed, then copy the finished document.

JSON Editor example

{
  "environment": "staging",
  "featureFlags": {"newSearch": false},
  "timeoutSeconds": 30
}

Try changing newSearch to true or timeoutSeconds to 60. Keep boolean and numeric values unquoted when those are the types your application expects.

Syntax checks and data representation

The tool uses JavaScript JSON parsing. Syntax validation does not check a schema or application rules. Formatting and minification parse and serialize the document: duplicate property names collapse to the last value, integer-like keys may reorder, and numbers beyond JavaScript’s safe integer range can lose precision. Keep long numeric identifiers as strings and retain your original source when exact representation matters.

JSON Editor questions

Are my edits saved after I leave the page?

No. The workspace does not save your JSON between visits. Copy your changes before refreshing, closing the tab, or opening another tool page.

Can I undo an edit?

The code editor supports standard keyboard undo and redo commands while you edit. Keep a separate copy of important source data before applying transformations.

Does valid JSON mean my configuration is correct?

No. Syntax validation only confirms that the document can be parsed. Your application may still require particular fields, types, or values.

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No server, no uploads

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Works offline

Once loaded, this tool keeps working with your Wi-Fi turned off. Try it.

Verify it yourself

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