JSON Formatter
Paste JSON, get clean, readable output — or the exact line where it broke.
Nothing is uploaded and nothing is kept after you leave the page.
01 Capability
What it does
Small details that make the job quicker.
- Validates first, then formats — and points to the line and column of a real syntax error.
- Formats with 2 spaces, 4 spaces or a tab, and minifies in one click.
- Handles large documents without uploading a single byte.
- Keyboard shortcut, sample data, copy and clear are all one press away.
- Keeps working offline once the page has loaded.
02 Questions
Questions
Short answers, no small print.
Is my JSON uploaded anywhere?
No. Formatting and validation run in your browser using the JSON parser built into JavaScript. Astra never receives your data, and nothing is stored after you close the tab.
Why did my JSON fail to parse?
Usually a trailing comma, a missing value, single quotes instead of double quotes, or a comment. The error box names the line and column so you can jump straight to it.
Can it handle large files?
Yes. A few megabytes format quickly because the work happens locally. Very large documents may make the browser pause for a moment while it renders the result.
What is the difference between Format and Minify?
Format adds indentation so the structure is readable. Minify removes all unnecessary whitespace to make the payload as small as possible, which is useful before you paste it into an API request.
Does it change my data?
No. Values, key order and types are preserved exactly. The output is your JSON, only with different whitespace.