მთავარი მიღებული
- 01Three actions in one pane: Format to pretty-print, Minify to collapse, Check to validate without changing the input.
- 02Choose 2-space, 4-space, or tab indentation to match your project's style.
- 03Validation uses the browser's native JSON parser and reports the exact position of any error.
- 04Your JSON never leaves your device — works offline once the page is loaded.
Why Developers Need a Fast JSON Viewer
API responses, config files, database exports, and log entries all arrive as JSON — often minified, oddly indented, or subtly broken. Reading a single-line JSON blob from a curl response is difficult. Chasing down a trailing comma error in a 500-line config file by eye is worse. A good JSON viewer handles both in seconds.
Handytool's JSON viewer gives you one large editable pane with three targeted actions. Format pretty-prints in your preferred style. Minify collapses to a single line for transport or comparison. Check parses without touching the input and reports the exact line and character where a parse error occurs. Everything runs in your browser using the native JSON engine — no upload, no account, no extensions.
How to View and Format JSON Online
- 01
Paste your JSON
Paste any JSON — an API response, config file, database dump, or log entry — directly into the editor pane.
- 02
Choose an indentation style
Switch between 2-space, 4-space, and tab indentation in the toolbar. The setting takes effect the next time you click Format.
- 03
Format, Minify, or Check
Click Format to pretty-print in place. Click Minify to collapse everything to one line. Click Check to validate without modifying the input — you'll see either a confirmation or the error position.
- 04
Copy or download the result
Copy the formatted or minified JSON to the clipboard, or download it as a .json file.
What You Can Do With the JSON Viewer
- 01Pretty-print minified JSON from an API response for easy reading
- 02Minify formatted JSON to a single line before embedding in code
- 03Validate a config file before committing or deploying
- 04Check that a copied JSON payload is well-formed before sending it to an API
- 05Reformat JSON to match your project's indentation convention
Your JSON Never Leaves Your Browser
The viewer uses the browser's built-in JSON.parse and JSON.stringify functions — no external library, no network request. Paste an API key, a private config, or a customer data export and it never leaves your device. Close the tab and the content is gone.
The tool works without a network connection once the page is loaded, making it useful in environments where internet access is restricted or when working with sensitive internal systems.
JSON Viewer FAQ
How do I format JSON online for free?
Paste your JSON into the editor, choose your indentation preference, and click Format. The pane updates in place with a pretty-printed version — no upload required.
What does the Check button do?
Check parses your JSON without modifying it. If it's valid you'll see a confirmation; if not, you'll see the exact error message and position where parsing failed.
Why is my JSON invalid?
Common causes are trailing commas, single quotes, unquoted keys, or comments — none of which are allowed by the JSON specification. The error message highlights where parsing failed.
Is my JSON sent to a server?
No. The viewer uses JavaScript's built-in JSON parser in your browser. Your data is never uploaded, logged, or stored.
Is there a size limit?
No hard cap. Very large documents may take a moment to render, but typical API responses and config files process instantly.
Is the JSON viewer free?
Yes. Every Handytool is free — no accounts, sign-ups, or usage limits.