Developer
JSON Formatter
Pretty-print or minify JSON, with validation that points at the exact line and column when it fails rather than just saying it is invalid. Handles large documents without locking the tab.
Runs entirely in your browser
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How it works
- 01Paste JSON into the left pane.
- 02It formats as you type, and points at the exact line and column if it cannot parse.
- 03Copy the result, or minify it back down.
Questions
- Are my files uploaded anywhere?
- No. The file is read from your disk by the browser and processed in this tab using JavaScript and WebAssembly. Nothing is transmitted, which you can verify by opening your browser's network panel or by disconnecting from the internet — the tool keeps working.
- Why does it show a line and column when browsers only give a character position?
- Because a character offset is useless when you are looking at a textarea. The position is converted to a line and column so you can actually find the problem.
- Is there a catch — a limit, a watermark, a sign-up?
- None. Because the work happens on your machine rather than a server, there is no per-file cost to recover and therefore nothing to meter. No account, no queue, no watermark.