JSON Editor
A real code editor with syntax highlighting, line numbers, folding and bracket matching. Paste anything — invalid JSON is auto-fixed on format.
{ } docs
JSON Formatter — Help & Guide
Everything about formatting, validating, and exploring JSON — the views, the syntax, the shortcuts, and the answers to common questions.
// quick start
Format JSON in four steps
- 1
Paste your JSON
Drop raw, minified or even slightly broken JSON into the editor — or use Open / Paste.
- 2
Format
Click Format (or press Cmd/Ctrl + Enter). Invalid JSON is auto-fixed where possible.
- 3
Explore
Switch tabs to view your data as a tree, graph, stats dashboard, diff, search or map.
- 4
Copy or download
Copy to the clipboard or download a .json file with Cmd/Ctrl + S.
// shortcuts
Keyboard shortcuts
Format JSON⌘/Ctrl+↵
Download .json⌘/Ctrl+S
// why use it
Built for developers
Instant formatting
Beautify minified or messy JSON in one click with clean, consistent indentation.
Real-time validation
Catch syntax errors instantly with clear, located messages while you type.
Smart auto-fix
Trailing commas, single quotes and unquoted keys are repaired automatically.
100% private
Everything runs in your browser. No servers, no tracking, no data ever leaves your machine.
// the workspace
Seven ways to work with JSON
Tree View
Explore JSON as a collapsible tree. Expand/collapse nodes and edit any key or value inline by clicking it.
Graph View
A hierarchical node graph of your data. Click nodes to expand or collapse branches; zoom, pan, and fit to screen.
Statistics
An analytics dashboard: total keys, values, depth, minified size, type distribution, nesting depth and most-frequent keys.
Diff View
Compare two JSON documents side by side. Differences update automatically with a git-style added / removed / modified breakdown.
Search & Filter
Search keys and values across the whole document, filter by type, and surface quick insights about your data.
Map View
Plot geographic data on an interactive map — GeoJSON, lat/lng pairs, or coordinate arrays are detected automatically.
// valid json
Valid JSON rules
JSON is strict. Most “broken” JSON comes from JavaScript or Python habits. These are the rules — and our formatter fixes the common slips automatically.
- Keys are double-quoted strings
{ "name": "Ada" } - Strings use double quotes (never single)
"hello" - No trailing commas
[1, 2, 3] - Values: string, number, boolean, null, object, array
true · 42 · null - No comments are allowed in strict JSON
—
// auto-fix
Common errors we fix
Single quotes
✗
{ 'a': 1 }✓
{ "a": 1 }Unquoted keys
✗
{ a: 1 }✓
{ "a": 1 }Trailing comma
✗
[1, 2, ]✓
[1, 2]Python literals
✗
{ "ok": True }✓
{ "ok": true }// questions
Frequently asked questions
What is a JSON formatter?▼
A tool that takes raw or minified JSON and re-indents it with line breaks so it is easy to read. Ours adds 2/4-space or tab indentation, organizes nested structures, and syntax-highlights the result.
What is JSON?▼
JSON (JavaScript Object Notation) is a lightweight, language-independent data-interchange format that is easy for humans to read and for machines to parse.
Is it free?▼
Yes — completely free and open source, with no signup, no ads, and no limits.
Is my data secure?▼
Absolutely. All processing happens 100% locally in your browser; nothing is ever uploaded, so it is safe for confidential data.
Can it fix invalid JSON?▼
Yes. The smart fixer repairs common mistakes — trailing commas, single quotes, unquoted keys and Python-style literals — when you format.
Can I validate JSON?▼
Validation runs as you type. The status bar shows valid/invalid plus node count, depth and size at a glance.
What can I do beyond formatting?▼
Explore data in Tree and Graph views, analyze it in Statistics, compare two documents in Diff, search and filter, and plot geographic data on a map.
// more json tools
Dedicated tool pages
Private & open source
A free, open-source tool for developers. Format, validate, and explore JSON instantly — every byte is processed locally in your browser, so your data never leaves your computer.
View source on GitHub