File
JSON Flattener
Turn nested objects and arrays into flat key paths (a.b.0.c) for spreadsheets and .env mapping, or rebuild nested structures from flat keys.
Runs entirely in your browser. Your data never leaves this device.
- Flatten nested JSON
- Unflatten paths
- Array indexes
- Copy output
- Private
Workspace
Client-side · No upload
How it works
- Adjust the controls or paste your input.
- Preview results instantly in the browser.
- Copy or download the output — nothing is uploaded.
Key features
- Flatten nested JSON
- Unflatten paths
- Array indexes
- Copy output
- Private
FAQ
Is this private?
Yes — processing runs in your browser; we do not upload your inputs.
Do I need an account?
No — free to use without signup.
Does it work offline?
After the page loads, most tools work without further network calls.
Mobile friendly?
Yes — layouts adapt to smaller screens.
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