JSON Formatter
Format, beautify, minify and validate JSON instantly — right in your browser.
100% private — everything runs in your browser
How to Use
- 1
Paste your JSON into the input editor or type it directly.
- 2
Click Format to pretty-print with the selected indentation, or Minify to collapse it into one line.
- 3
Click Validate to check the syntax — errors are reported with line, column and exact position.
- 4
Copy the result with one click, or download it as a .json file.
- 5
Press Reset to clear both editors and start over.
Examples
Pretty-print a compact object
Input
{"name":"ToolStack","tools":["json-formatter"],"free":true}Output
{
"name": "ToolStack",
"tools": [
"json-formatter"
],
"free": true
}Minify a nested object
Input
{
"user": {
"id": 1,
"roles": ["admin", "dev"]
},
"active": true
}Output
{"user":{"id":1,"roles":["admin","dev"]},"active":true}FAQ
What does a JSON formatter do?
A JSON formatter rewrites compact or messy JSON with consistent indentation so it is easier to read, review and debug. The same parser also detects syntax errors.
Is this JSON formatter free?
Yes, it is completely free — no sign-up, no limits and no ads covering the tool.
Is my JSON data sent anywhere?
No. Formatting, minifying and validation all run locally in your browser. Your JSON never leaves your device.
Why is my JSON invalid?
Common causes are missing commas, unquoted keys, trailing commas, single quotes or unescaped characters. The error message shows the exact line, column and position.
Can it handle large JSON files?
Yes. The editor is built on CodeMirror, which comfortably handles documents of several megabytes on modern devices.
Does it support comments or JSON5?
No — strict JSON does not allow comments. Remove them before formatting, or the validator will flag them as errors.