Is my JSON data sent to a server?
No. All processing happens entirely in your browser using JavaScript's built-in JSON.parse() and JSON.stringify(). Your data never leaves your device, making this tool safe for sensitive API keys, config files, and private data.
What does the Repair feature fix?
Repair handles the most common reasons JSON fails to parse: trailing commas (e.g. {"a":1,}), JavaScript-style comments (// and /* */), and single-quoted strings (common when copying from Python dicts). It's ideal for fixing hand-edited configs or JavaScript object literals.
What does Sort Keys do?
Sort Keys recursively sorts all object keys alphabetically throughout the entire JSON structure. This makes it easy to compare two JSON objects visually, find keys quickly, and produce deterministic output.
Can I use tabs instead of spaces for indentation?
Yes. Use the Indentation dropdown to choose between 2 spaces, 4 spaces, or tab characters. The setting is remembered for your next visit.
Why doesn't JSON to CSV work for my data?
CSV export requires a JSON array of objects at the root level. If your root is a plain object ({}), you'll need to wrap it in an array first. Arrays of primitives (strings, numbers) are also supported and produce a single-column CSV. Nested objects within rows are preserved as JSON strings in their cell.
Why am I getting "Unexpected token" errors?
Common causes include trailing commas (not allowed in JSON), single quotes instead of double quotes, unquoted keys, or comments. Try clicking Repair — it automatically fixes all of these. The error message also shows the exact line and column to help you locate the issue manually.
Is there a file size limit?
There is no hard limit. Very large files (over ~50 MB) may slow down your browser since everything runs client-side. The Tree Explorer uses lazy rendering so even large nested structures open quickly — deep nodes only render when you expand them.