Online JSON Viewer & Formatter

JSON (JavaScript Object Notation) is the format most APIs, configuration files and databases use to exchange data. Machines read it easily, but people struggle when a response arrives as one unbroken line of brackets and quotes. A JSON viewer fixes that: it lays the data out with indentation, colours each type of value, and lets you fold and unfold nested objects so you can see the shape of the data at a glance.

This online JSON viewer does all of that in your browser, and adds a JSON formatter, a JSON validator and an automatic repair tool. There is nothing to install and no account to create. Open the page, paste your JSON and start reading.

How to use the JSON viewer online

1. Add your JSON. Paste it into the editor, press Open to choose a file, drag a .json file onto the page, or use URL to load it straight from an API endpoint. Sample loads an example if you just want to try it.
2. Check the status. The badge above the editor says Valid JSON or tells you how many errors there are and on which line.
3. Format it. Press Format or Ctrl/⌘ + Enter to beautify the text in place.
4. Explore it. Switch to the Tree tab to browse the structure, search it and copy the path to any value.
5. Take it with you. Copy the result, download it as a file, or create a share link.

Using the JSON viewer online is the fastest way to inspect data from an API response, a log line or a config file without opening an editor or writing a script.

A JSON formatter online, built in

Minified JSON is small but hard to read. The built-in JSON formatter rewrites it with consistent line breaks and indentation without changing a single value. The Formatted tab updates as you type, and you can choose two spaces, four spaces or tabs. Turn on Sort keys to order every object alphabetically, which makes two versions of the same data easy to compare in a diff.

Many tools quietly round long numbers such as 64-bit database IDs. This JSON formatter online works on the original text, so every digit survives. When you need the opposite, Minify strips all whitespace and shows how many bytes you saved. For a page focused purely on pretty-printing, use our online JSON formatter or the JSON minifier.

A JSON validator that explains every error

Invalid JSON is the most common reason a formatter fails, and most tools only say “invalid input” or nothing at all. TheJSON validator here checks your text as you type. It underlines the problem, puts a red marker in the gutter, and explains it in plain English along with the exact line and column.

It recognises the mistakes that cause nearly every “Unexpected token” error:

• trailing commas after the last item in an object or array
• single quotes or curly “smart” quotes instead of straight double quotes
• unquoted keys, as in JavaScript object literals
• // and /* */ comments
• missing commas, colons and closing brackets
• Python-style True, False and None

Click any error in the list to jump to it. Press Fix and the JSON repair tool corrects these problems automatically. One undo restores the original if you want to fix it yourself. You can also use the dedicatedJSON validator page, or read our guide tocommon JSON syntax errors.

Explore large JSON with the tree view

Deeply nested data is easier to understand as a tree. Each object shows how many keys it has and each array how many items, and values are coloured by type. You can expand everything, collapse everything, or open the tree to a chosen depth. Search covers every key and value in the document, not just the rows on screen, and steps through the matches one by one.

Click any node to see and copy its JSONPath, such as $.orders[3].customer.email, ready for code, tests orjq filters. The tree only draws the rows you can see, so files of ten megabytes or more stay smooth. Try theJSON tree viewer, or learn the syntax in What is JSONPath?

Your JSON stays on your device

Your data never leaves your device. Parsing, formatting and validation all run in JavaScript inside your browser, and there is no server that receives or stores what you paste. Share links keep the JSON in the part of the URL after the #, which browsers never send to a server. Your current draft is saved only in your own browser, so it is still there next time. See theprivacy policy for details.

Why choose this online JSON viewer

• Errors are explained. You see what is wrong and where, instead of a silent failure.
• No clutter. No ads, pop-ups or sign-up walls between you and your data.
• Built for big files. Validation runs in a background thread and the tree stays responsive.
• Accurate output. Numbers, key order and string escapes are preserved exactly.
• Comfortable to use. Light and dark themes, keyboard shortcuts, line numbers, code folding and a layout that works on phones.

Who uses a JSON viewer?

Developers use it to debug API responses and webhooks. QA engineers use it to check test fixtures, and data analysts to understand exports before loading them elsewhere. DevOps teams use it to tidy configuration files, and students use it to learn how JSON is structured. If you work with JSON, a reliable JSON viewer, JSON formatter and JSON validator in one tab saves time every day.