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JSON Formatter

Format or minify JSON instantly. Everything runs in your browser — no data is uploaded.

How to use

  1. Paste your JSON into the textarea above
  2. Press "Format (2 spaces)" or "Format (4 spaces)" to pretty-print it
  3. Press "Minify" to strip all whitespace into a single line
  4. Use the "Copy" button to copy the result

Your data is processed entirely inside your browser and never sent to a server.

Example

Input:

{ "name": "Taro", "age": 30, "tags": ["a", "b"] }

Output of "Format (2 spaces)":

{
  "name": "Taro",
  "age": 30,
  "tags": ["a", "b"]
}

FAQ

Can it handle large JSON files?

Processing happens in browser memory, so files up to a few megabytes work smoothly. Extremely large files may slow down.

Is my data stored anywhere?

No. Everything runs in your browser and disappears when you reload the page.

What happens if my JSON is invalid?

An error message is shown. Check for missing commas or quotes based on the message.

Category:Developer
Tags:jsonformatterdeveloper
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