What is the json formatter?
The JSON Formatter beautifies, validates and minifies JSON instantly, and when input is broken it pinpoints the exact error line and column with a jump-to-error link. It also supports key sorting and live editing. Free and fully in-browser, so your JSON is never uploaded or stored anywhere.
The GigAI JSON Formatter is a desktop-grade JSON editor that runs entirely in your browser. Paste, drop or type JSON and it beautifies with 2-space, 4-space or tab indentation, minifies to the most compact form, sorts every object key alphabetically for clean diffs, and validates as you type. What sets it apart from jsonformatter.org and JSONLint is the error experience: when your JSON is invalid we surface the precise line and column, explain what the parser expected, and give you a one-click jump straight to the offending character. No more counting braces by hand. It shows the byte size before and after so you can see exactly what minifying saved, keeps a full undo/redo history, and works from the keyboard with real shortcuts. Because everything happens locally with the browser's native JSON engine, your payloads (API responses, tokens, config, customer data) are never uploaded, logged or seen by anyone. Close the tab and it's gone.
- Difficulty:
- Easy
- Typical time:
- ~15s
- Processing:
- 100% browser processing
Last updated
How to use the json formatter
- 1
Paste, drop or import JSON
Paste into the left editor, drag a .json file onto it, or click to browse. Or load a built-in sample to try it instantly.
- 2
Pick a mode & indent
Choose Beautify, Minify or Sort keys, and set 2-space, 4-space or tab indentation. Everything re-runs live as you change options.
- 3
Fix any errors
If the JSON is invalid, read the exact line and column in the error banner and click Jump to error to place your cursor on it.
- 4
Copy, download or share
Copy the formatted output, download it as a .json file, or share a link that reopens the tool with your input pre-loaded.
What JSON Formatter includes
Exact error line & column
When JSON won't parse we show the precise line and column, quote what the parser expected, and give you a one-click jump to the character, far beyond a generic 'unexpected token'.
Beautify, minify or sort
Pretty-print with 2-space, 4-space or tab indentation, collapse to the most compact one-liner, or alphabetise every object key for clean, reviewable diffs.
Live as you type
Formatting and validation run on every keystroke with a smart debounce, so the output pane and error banner stay in sync without a 'Format' button dance.
Byte size before & after
See the input and output size and the exact percentage saved when you minify, so you know what a build or payload trim actually buys you.
Drop, paste or import
Drag a .json file onto the editor, paste from your clipboard, or click to browse. Copy, download or share a link to the result with one click.
100% in your browser
Parsing uses the browser's native JSON engine on your device. No API response, token or config file is ever uploaded, stored or logged.
Why use our json formatter
Debug broken JSON in seconds
The pinpoint line/column locator and jump-to-error turn a cryptic parse failure into a two-second fix, instead of manually counting brackets in a wall of text.
Clean diffs with sorted keys
Sorting keys alphabetically makes two JSON blobs comparable in Git, so code review focuses on real changes rather than reshuffled fields.
Trim payloads for production
Minify config and fixtures and watch the byte savings, shaving weight off bundles, cache entries and API responses without touching the data.
Private by design
Because it runs locally, you can safely format JSON containing secrets, PII or internal API shapes, none of it leaves your machine.
Built for the way you work
From quick one-off fixes to daily workflows, see how people put this tool to use.
- Backend developer
Inspect an API response
Paste a minified API payload from your network tab to read it structured, then sort keys to diff two responses and spot exactly what changed.
- Frontend developer
Fix a config that won't parse
When a package.json, tsconfig or i18n file throws on load, jump straight to the trailing comma or unquoted key the parser is choking on.
- QA / Data engineer
Validate fixtures and exports
Confirm a data dump or test fixture is valid JSON before it hits a pipeline, and minify large fixtures to keep repositories lean.
- Student
Learn JSON structure
Beautify a compact example to see how objects, arrays and nesting fit together, with instant, plain-language feedback when something is malformed.
Supported formats
Accepts JSON and TXT, and produces JSON, all processed locally in your browser.
- JSON
- TXT
- JSON
Frequently asked questions
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JSON Validator
Validate JSON against RFC 8259 with the exact error line, column and a caret under the bad character. Get plain-English explanations, one-click auto-fix for trailing commas and single quotes, plus depth, key-count and type stats, nothing uploaded.
JSON to CSV
Convert JSON to CSV in your browser. Paste an array of objects and get a spreadsheet-ready CSV with a header row, automatic flattening of nested keys, and a choice of comma, semicolon or tab delimiter. Copy or download instantly. Nothing is uploaded.
JSON Diff
Compare two JSON documents by structure, not text. Reordered keys and whitespace are ignored. You see added, removed and changed values by path with counts, all in your browser.
JSON Tree Viewer
Explore JSON as an interactive, collapsible tree. Expand or collapse any branch, see type and array-length badges, search keys and values with live highlighting, and copy any node's value or its JSONPath in one click, all 100% in your browser.
Use JSON Formatter in your code
The same engine runs behind the free API: send files, get signed download links back, and everything is deleted after the retention you choose. 1,000 tasks a month, no card.
Also runs as a task inside a job - chain it with the other engines. See the recipes.
curl -X POST https://api.gigai.tools/v1/jobs \
-H "Authorization: Bearer $GIGAI_API_KEY" \
-H "Content-Type: application/json" \
-d '{ "tasks": {
"in": { "operation": "import/url", "url": "https://example.com/input.json" },
"work": { "operation": "format-json", "input": ["in"] },
"out": { "operation": "export/url", "input": ["work"] }
} }'
# then poll until finished and follow the export URL:
curl https://api.gigai.tools/v1/jobs/JOB_ID/wait -H "Authorization: Bearer $GIGAI_API_KEY"Comparisons & guides
Go deeper on the concepts behind the json formatter.
CSV vs JSON: Which Data Format Fits Your Job?
ComparisonCSV is a flat, compact table format that spreadsheets love. JSON is a nested, structured format that code and APIs love. How to do it they differ and when to reach for each.
Read the comparisonJSON vs XML: Which Should You Use for Data Exchange?
ComparisonJSON is lean, fast to parse and the default for modern web APIs. XML is verbose but self-describing, with schemas, namespaces and rich validation. Here's the real trade-off.
Read the comparisonYAML vs JSON: Which Is Better for Config and Data?
ComparisonYAML is human-friendly with comments and clean indentation, ideal for config. JSON is strict, ubiquitous and data-exchange-ready. Here's when each wins, and the gotchas.
Read the comparisonHow to Format JSON (Pretty-Print & Validate)
GuideTurn a minified or broken JSON string into clean, indented, readable JSON, and catch syntax errors while you're at it. A quick step-by-step guide.
Read the guideHow to Convert CSV to JSON (Free, In Your Browser)
GuideTurn a spreadsheet or CSV export into a clean array of JSON objects, with the right headers as keys and correct data types. A step-by-step guide.
Read the guideHow to Decode a JWT (Read Its Header & Payload)
GuidePaste a JSON Web Token and read its header and claims in plain JSON, inspect the algorithm, expiry and scopes while debugging auth. A safe, browser-only guide.
Read the guideCommon problems, solved
Hit a snag? Here are quick fixes for the issues people run into most.
It says 'Unexpected token' but the JSON looks fine.
Click Jump to error and inspect the reported line/column. The usual culprits are a trailing comma after the last item, a single quote instead of double, or an unquoted key. JSON is stricter than JavaScript object literals.
My large numbers changed after formatting.
JSON.parse coerces numbers to IEEE-754 doubles, so integers above 2^53−1 (like some Twitter/Snowflake IDs) lose precision on any round-trip. Keep such IDs as strings in the source to preserve them exactly.
Nothing happens on a huge paste.
Very large inputs (multi-megabyte) are guarded to keep the tab responsive. Trim the payload, or format it in sections. The limit is generous but not unbounded.
My comments disappeared.
Standard JSON has no comments, so the parser rejects them. If you're editing JSONC (VS Code settings, tsconfig), strip the comments first. This tool validates strict RFC 8259 JSON.
Get the most out of it
Use Sort keys before committing generated JSON so future diffs stay small and reviewable.
Press Ctrl/Cmd+Enter to re-run instantly, and Ctrl/Cmd+S to download the formatted output.
Minify then check the byte-size badge to see the exact savings before shipping a payload or fixture.
Getting a parse error at the very end? It's almost always a trailing comma or a missing closing brace/bracket.
Store big numeric IDs as strings to avoid silent precision loss on the parse/stringify round-trip.
What's new
Recent updates and improvements to the json formatter.
Initial release: live beautify/minify/sort, 2/4/tab indentation, precise line + column errors with jump-to-error, byte-size stats, drag-drop import, undo/redo and shareable links.
Added keyboard shortcuts (run, download, clear, undo/redo) with an in-tool shortcuts helper, plus a curated set of sample documents.
Improved big-integer precision guidance and refined error messages for trailing commas and unquoted keys.
Keep exploring
Problems we solve
Definitions
From the blog
- How to Find Exposed API Keys in Your Code (Before Someone Else Does)
- How to Generate TypeScript Types from JSON (API Responses Made Type-Safe)
- How to Fix Invalid JSON Errors: The Complete Troubleshooting Guide
- How to Convert CSV to JSON: Headers, Types, and Nesting Done Right
- What Is JSON and How to Read It: A Beginner's Guide
Explore categories
Compare formats
By file type
Common tasks
Your privacy is built in
Your JSON is parsed and formatted entirely in your browser using its native JSON engine. It is never uploaded to any server. Nothing is stored, logged or transmitted, so you can safely paste responses containing tokens, keys or personal data. Close the tab and every trace is gone.
- Runs in your browser
- No uploads
- Nothing stored
Ready to try the json formatter?
Free, private and instant. JSON Formatter runs right in your browser.