Glarso

JSON Formatter & Validator

Format, minify, and validate JSON with clear error messages. Nothing leaves your browser.

Format and validate JSON without leaking it

Paste raw JSON — an API response, a config file, a log entry — and format it into readable, indented structure or minify it down to one line. Invalid JSON gets a clear error message with the line number, not just a red X.

Most online JSON tools send your data to their servers. Given how often JSON contains secrets and personal data, this one deliberately doesn't: parsing, formatting, and validation all run in your browser.

Frequently asked questions

Is my JSON sent anywhere?

No — and that matters here more than most tools. JSON pasted into formatters often contains API keys, tokens, and customer data. This one parses everything locally in your browser.

How do I find what's wrong with invalid JSON?

Click Format and the parser reports the exact problem with its line number — a trailing comma, missing quote, or unescaped character. Fix it and format again.

What's the difference between Format and Minify?

Format pretty-prints with indentation for reading; Minify strips all whitespace into a single line for the smallest payload. Both validate the JSON first.

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