Online JSON formatter, beautifier, and validator
JSONKitt is a free JSON formatter and validator you can use without an account. Paste JSON, upload a .json file, or load a sample payload. Beautify JSON with spaces or tabs, identify syntax errors with line and column details, then minify, explore a tree view, or convert JSON to CSV, XML, or YAML.
Everything runs directly in your browser using JavaScript. Your JSON is not sent to our servers during normal processing, and no account or database is required. API fetching and share links are optional features that you control.
Learn more with What is JSON or explore a realistic JSON example.
Frequently asked questions
- What is an online JSON formatter?
- A JSON formatter (also called a JSON beautifier) takes compact or messy JSON and reprints it with consistent indentation so objects, arrays, and keys are easy to read. JSONKitt formats JSON in your browser with JSON.parse and JSON.stringify — the document is not uploaded.
- Is this JSON formatter also a JSON validator?
- Yes. If the input is invalid, you get the exact line and column of the parse error, the same job a JSONLint-style validator does. Fix the syntax, then format, minify, or convert.
- Does JSONKitt upload my JSON?
- No. Format, validate, minify, tree view, and converters run locally. The only extras that leave the tab are an optional API fetch you start yourself, or a share link that packs data into the URL.
- How do I beautify JSON online?
- Paste JSON into the input editor (or drop a .json file), choose 2/3/4 spaces or tabs, then click Format or press Ctrl/Cmd+Enter. Copy or download the pretty-printed output. Turn on Auto-format to re-beautify as you type.
- Can I convert formatted JSON to CSV, XML, or YAML?
- Yes. Use JSON to CSV, JSON to XML, and JSON to YAML. You can also generate TypeScript, Pydantic, and Java/Kotlin types from a sample payload.