JSON Formatter & Validator
Beautify, minify and validate JSON with precise error positions.
{
"name": "veojson",
"tools": [
{
"slug": "jwt-decoder",
"free": true
}
],
"stars": 42
}JSON, YAML & Data Wrangling Cheat Sheet
25 jq recipes, JSONPath syntax, reusable JSON Schema patterns and the YAML gotchas that break pipelines.
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About this tool
This JSON formatter parses your input entirely in the browser — nothing is uploaded to a server. It pretty-prints valid JSON with configurable indentation, minifies it back to a single line, and reports the exact character position of any syntax error so you can fix broken payloads fast.
How to format JSON online
Paste your raw JSON into the input panel. The formatter validates as you type and re-indents the document with two or four spaces. Use Minify when you need the smallest possible payload for an API request or a config value.
Why is my JSON invalid?
The most common causes are trailing commas, single quotes instead of double quotes, unquoted object keys, and unescaped newlines inside string values. The error message shows the offending position so you can jump straight to it.
How to use JSON Formatter & Validator
- 1
Open JSON Formatter & Validator
Everything runs on this page — there is nothing to install and no account required to use the free features.
- 2
Add your input
Paste or enter your values in the panel above. The tool updates as you type, so you can iterate quickly.
- 3
Review the output
Check the result, copy it with one click, and adjust the options until it matches what your system expects.
- 4
Take it further
Use the utility & formatting tips below to make the result production-ready, then unlock the gated extras via the form above.
Best practices
- Store and transmit minified JSON; format only for human reading. Whitespace is pure bandwidth cost on the wire.
- Validate payloads against a JSON Schema in CI rather than eyeballing them — the formatter catches syntax, schema catches meaning.
- Keep keys stable and lowercase-with-underscores or camelCase, but never mix both in one API.
- Never paste customer data or secrets into any online formatter unless, like this one, it parses fully in the browser.
- Prefer UTF-8 without a BOM; a stray BOM is the most common cause of an 'unexpected token' at position 0.
Why JSON Formatter & Validator matters
Formatting and conversion chores are individually trivial and collectively enormous — they quietly consume hours of engineering time every week.
Doing them instantly and consistently removes a whole category of copy-paste mistakes.
Related free & paid tools
| Tool name | Type | Key features | Link |
|---|---|---|---|
| JSONLint | Free | Browser JSON validator with error positions | Visit |
| Prettier | Free | Formats JSON, JS and YAML in your editor and CI | Visit |
| JSON Crack | Freemium | Turns JSON into an explorable node graph | Visit |
| JetBrains WebStormOffer | Paid | IDE with JSON schema validation and reformat-on-save | Visit |
Links marked Offer may be partner links. They cost you nothing extra and never affect which tools we recommend.