JSON Formatter
Read minified JSON, see parse errors, and tidy the document in this tab. Nothing is uploaded.
Processed in your browser
Format, minify, and validate run in this browser. We do not send the document body.
Drop a JSON file here, or paste below.
Advanced options
Paste JSON or load a file, then format.
Formatted JSON will appear here.
Features
Format
Pretty-print JSON with 2 or 4 space indent.
Minify
Strip insignificant whitespace into a single line.
Validate
Check standard JSON and return a readable parse error.
Local files
Load and download on this device. Files are not uploaded.
How to use
- Paste JSON or drop a local file.
- Choose Format. Minify and Validate are available when you need them.
- Copy the result or download it.
Why this tool
Runs in the browser
Core work finishes in this tab.
No upload
Pasted text and local files are not sent away for processing.
Free, no account
The core path has no signup wall.
Immediate
There is no upload-and-wait queue.
Japanese and English
The same tool ships at / and /en/.
Readable failures
Broken input returns a reason, not a blank screen.
FAQ
- Is my JSON uploaded?
- No. Format, minify, and validate all run in this browser.
- Can I use JSON with comments?
- No. Only standard JSON (JSON.parse). Comments and trailing commas are errors.
- How large can the input be?
- Up to your device memory. Tens of MB may freeze the tab.
- Will key order change?
- Usually not. We rely on typical JSON.parse insertion order.