JSON Formatter – Beautify, Minify & Explore JSON Online
Format, beautify & validate JSON instantly. Client-side only — your data never leaves your browser.
Ctrl + Enter to format • Drop a .json file anywhere to load
What is JSON?
JSON (JavaScript Object Notation) is a lightweight data interchange format. It's easy for humans to read and write, and easy for machines to parse and generate. JSON is built on two structures: a collection of name/value pairs (objects) and an ordered list of values (arrays). It has become the de facto standard for API communication and configuration files across the web.
Why use this JSON Formatter?
This free JSON formatter lets you beautify, minify, sort, and validate JSON instantly. Paste your JSON and press Format: syntax highlighting, indentation control, and precise error reporting appear in milliseconds. Everything runs 100% in your browser — your data never leaves your device, so there is no server round-trip, no queue, and no exposure of sensitive payloads. Speed is limited only by your machine.
Beyond formatting, the tool doubles as a JSON explorer: switch to Tree View to collapse and search deeply nested structures, or Table View to scan arrays row by row. Sort keys alphabetically for stable diffs, see byte-size stats for every transformation, and copy or download the result in one click. Use Open in to send the same document straight to the Validator, Minifier, Diff, or any of the other 10 tools without re-pasting.
How to use this formatter.
- Paste or type your JSON into the input editor on the left
- Click "Format" or press Ctrl+Enter to beautify
- Copy or download the formatted output
You can also drag & drop a .json file, or fetch JSON from a URL using the toolbar.
Features.
Fast JSON Formatting
Format JSON in milliseconds with configurable indentation
100% Private
All processing happens in your browser — nothing is sent to any server
Syntax Highlighting
Beautiful color-coded syntax with light and dark themes
Validation
Real-time error detection with line and column numbers
File Support
Drag & drop JSON files or fetch from URLs
Full Toolkit
Minify, diff, convert to YAML/CSV/TypeScript, and more
Related JSON tools.
jsons.site is a full client-side JSON toolkit. Common next steps after formatting:
- JSON ValidatorJSON validator with line and column errors
- JSON Repairrepair broken JSON automatically
- JSON Minifierminify JSON and see size savings
- JSON Viewerexplore nested data in the tree viewer
- JSON Diffdiff two JSON documents side by side
- JSON Schema Validatorvalidate against a formal JSON Schema
- JSON Path Finderquery nested values with the JSONPath finder
- JSON → YAMLconvert JSON to YAML and back
- JSON → CSVflatten a JSON array into CSV
- JSON → TypeScriptgenerate TypeScript interfaces from JSON
FAQ.
Is my data safe?
Absolutely. All JSON processing happens entirely in your browser using JavaScript. Your data is never transmitted to any server.
Is this JSON formatter free?
Yes. All 11 tools on jsons.site are completely free with no usage limits, accounts, or watermarks.
What's the maximum file size?
There's no hard limit, but performance is best with files under 10MB. For very large files, the browser's memory is the only constraint.
Can I format invalid JSON?
The formatter will show you exactly where the error is with line and column numbers, helping you fix the issue quickly. For automatic repair, use the linked JSON Repair tool.
What's the difference between formatting and minifying JSON?
Formatting (pretty-printing) adds indentation and newlines for readability. Minifying removes all optional whitespace to reduce payload size for production and API responses.
Does it support JSON with comments (JSONC)?
The formatter validates strict JSON (RFC 8259), so comments are flagged as errors — but your content still displays. Use JSON Repair to strip comments automatically.
Looking for a different transformation? Explore thefull JSON toolkit— 11 free, private, in-browser tools that never upload your data.