JSON to CSV

Flatten the JSON.

Rows and columns. Instantly.

JSON
CSV
Delimiter:
0 rows · 0 columns
No upload
Works offline
No tracking

Need to convert large JSON files? The offline bundle handles unlimited files with no limits. $49 once.

Get Bundle →
// How it works

Three steps. Zero uploads.

01
Paste
Paste your JSON array. It stays on your device.
02
Convert
fwip extracts keys as headers and values as rows. Nested objects are flattened.
03
Download
Copy the CSV or download as .csv. Nothing was ever uploaded.
// Why this is different

Your data never leaves your machine.

Most online converters upload your data to a server. Your JSON passes through systems you don't control.

fwip works differently. The conversion engine runs entirely in your browser. Your data is read from your device, processed on your CPU, and the result is saved back to your device. No server is involved. We literally cannot see your file.

No server processing

Everything runs on your device using WebAssembly. Your file never touches a network.

No account required

Drop a file. Get a result. No sign-up, no email, no password.

No subscription

Free in the browser. $99 once for the offline bundle. That's it. Forever.

Works offline

The desktop version works with no internet connection at all.

// Questions

Frequently asked.

What JSON structure is supported?▾
fwip expects a JSON array of objects, like [{...}, {...}]. Each object becomes a row, and object keys become column headers.
How are nested objects handled?▾
With "Flatten nested" enabled, nested objects like {"address": {"city": "Sydney"}} become flat columns like "address.city".
What about arrays inside objects?▾
Array values are serialized as JSON strings in the CSV cell. For example, [1, 2, 3] becomes "[1,2,3]" in the cell.
Can I convert CSV back to JSON?▾
Yes. Toggle the direction to "CSV → JSON" to convert comma-separated data back to a JSON array of objects.
What delimiters are supported?▾
Comma (default), tab, and semicolon. Choose the delimiter that matches your target application.
// Related tools

You might also need.

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 DATA
CSV to SQL
Generate SQL INSERT statements from CSV data.

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