Free JSON Formatter & Validator

The JSON Formatter is a free online tool that formats, validates, and beautifies JSON data with proper indentation and syntax highlighting.

Yes, it is completely free with no registration required. All formatting happens client-side in your browser.

Yes, the JSON Formatter validates your JSON syntax and shows clear error messages if there are any issues, helping you quickly find and fix problems.

Absolutely. The JSON Formatter & Validator processes everything client-side in your browser. No data is uploaded to or stored on any server. Your content remains private on your device at all times.

Yes, the JSON Formatter & Validator is fully responsive and works on smartphones and tablets. You can use it on any device with a modern web browser -- no app download required.

No account or registration is needed. Simply open the JSON Formatter & Validator in your browser and start using it immediately. There are no sign-up walls or usage restrictions.

Simply enter your input in the provided field, adjust any settings to your preference, and the tool will process it instantly. You can then copy the result to your clipboard or download it.

The JSON Formatter & Validator works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera. For the best experience, use the latest version of your preferred browser.

Formatting (also called beautifying or pretty-printing) adds line breaks and consistent indentation so the structure of objects and arrays is easy to read, which is ideal when debugging API responses or reviewing configuration files. Minifying does the opposite: it strips all unnecessary whitespace and line breaks to produce the smallest possible file, which reduces payload size when JSON is sent over the network or stored. Both outputs contain exactly the same data — only the whitespace changes — and this tool can convert between the two with one click, so you can work with a readable version and ship a compact one.

The most frequent JSON errors are trailing commas after the last item in an object or array, single quotes instead of the required double quotes around strings and keys, unquoted property names, missing commas between items, and unescaped special characters such as line breaks or backslashes inside strings. JavaScript-style comments are also invalid, because the JSON specification does not allow them. When validation fails, this tool reports the line and position of the first problem so you can jump straight to it, fix it, and re-validate until the document parses cleanly.

Yes. You can choose how many spaces are used for each indentation level before formatting. Two spaces is the most common convention in web development and keeps deeply nested structures compact, while four spaces gives more visual separation and can be easier to scan in large documents. Whatever you pick affects only presentation — the underlying data is untouched — so you can reformat the same JSON repeatedly with different settings until it matches your team’s style guide.

Yes, the formatter can reorder the keys of every object in your document alphabetically. Sorted keys make it much easier to compare two JSON files in a diff tool, spot duplicate or missing properties, and keep configuration files consistent across a project. Because the JSON specification treats objects as unordered collections, sorting keys does not change the meaning of the data — any standards-compliant parser will read the sorted document exactly the same way.

Yes. In addition to the text output, the tool can display your JSON as an interactive, collapsible tree. The tree view lets you expand and collapse nested objects and arrays, which makes it far easier to explore large API responses or deeply nested configuration files than scrolling through raw text. It is especially useful when you only need to inspect one branch of a large document, such as a single record inside a long results array.

JSON looks like JavaScript object syntax but is a much stricter format. JSON requires double quotes around all strings and property names, forbids comments, trailing commas, undefined, NaN, and Infinity, and only permits a small set of value types: objects, arrays, strings, numbers, booleans, and null. An object literal that runs fine in JavaScript — for example one with unquoted keys or single-quoted strings — is therefore often invalid JSON. The validator follows the official JSON specification (RFC 8259), so anything it accepts will parse in every mainstream language and API.

Because all processing happens locally in your browser, the practical limit depends on your device’s memory rather than any server quota. Documents up to several megabytes — typical API responses, logs, and configuration files — format and validate almost instantly on a modern computer. Very large files of tens of megabytes may take a few seconds or feel slow in the tree view, in which case minified output and a fast machine help. There is no fixed upload cap, no rate limit, and nothing ever leaves your device.

Yes. The formatted output is standard JSON that any programming language, framework, or API can consume — formatting only changes whitespace, never the data. Once the document validates, you can copy it to your clipboard or download it as a .json file and use it directly in JavaScript with JSON.parse, in Python with the json module, in REST API request bodies, or in configuration files. Validating here first is a quick way to rule out syntax problems before your application ever sees the data.

JSON is a strict format defined by RFC 8259: every string and property name must use double quotes, comments are forbidden, and trailing commas, single quotes, and unquoted keys all cause a parse error. JSON5 is a relaxed superset designed to be easier for humans to write and maintain. It allows single-line and block comments, trailing commas after the last item, unquoted object keys, single-quoted strings, and a few other conveniences borrowed from JavaScript. JSON5 is popular for hand-edited configuration files, but most APIs and parsers still expect strict JSON. This tool has a JSON5 toggle: switch it on and the formatter tolerates those relaxed conventions, converting comments, trailing commas, unquoted keys, and single quotes into strict, standards-compliant JSON before it formats the output. Paste your config above and enable JSON5 to clean it up.

You can generate TypeScript interfaces directly from sample JSON instead of typing them by hand. The tool inspects every object, array, string, number, boolean, and null in your document and infers a matching type, then emits named interfaces for each nested object so the whole shape is fully typed. Switch to the TypeScript tab after pasting valid JSON, and you get ready-to-copy interface definitions you can drop straight into your codebase. This is a fast way to type an API response, a config file, or a webhook payload without guessing field names or nesting. Because the types are inferred from real data, scan optional or nullable fields afterward — a sample may not include every possible key. You can copy or download the result. Paste a JSON example above and open the TypeScript tab to generate interfaces instantly.

When you are debugging a deeply nested API response, locating the exact path to one value by scrolling raw text is slow and error-prone. Use the interactive tree view: it renders your JSON as a collapsible structure where you can expand only the branches you care about. Click any value and the tool copies its path in JSONPath-style notation — for example $.users[0].email — so you know precisely how to reach that field. That path is exactly what you need when writing JSONPath queries, test assertions, or code that extracts a specific property from a response. It saves you from manually counting array indices or tracing nested keys, and you can collapse the branches you do not need so only the relevant part of the document stays on screen. Paste your JSON above, switch to the tree view, and click a value to grab its path with one click.

To see exactly how two JSON documents differ, use the diff feature instead of scanning both files side by side. Paste your original JSON, then paste a second document to compare against it, and the tool performs a deep, structural comparison rather than a plain text match. It walks both documents and reports every value that was added, removed, or changed, grouping each result by its path so you can pinpoint the location of a difference even in deeply nested objects and arrays. This is far more reliable than a line-based text diff, which gets confused by reordered keys or reformatted whitespace. Tip: sorting keys alphabetically on both documents first makes the comparison even cleaner. It is ideal for spotting config drift between environments or checking what an API response changed between versions. Paste two documents above to diff them.

You can turn any valid JSON document into a JSON Schema automatically rather than writing the schema by hand. The tool analyzes your data and produces a draft-07 schema that describes the structure: the type of every field, the properties of each object, and the item type of each array. Open the schema tab after pasting valid JSON and you get a copyable, downloadable schema you can use to validate future payloads, document an API contract, or drive code generation and form builders. Because the schema is inferred from one example, review it before relying on it — a single sample cannot reveal which fields are optional, what enum values are allowed, or the full range of a number, so you may want to loosen or tighten constraints manually. It is a strong starting point that saves most of the boilerplate. Paste your JSON above and open the schema tab to generate it.