JSON 포맷터 — 무료 온라인 도구
즉시 사용, 무료, 회원가입 불필요. 파일은 로컬에서 처리되며 업로드되지 않습니다.
By the AllFileBox Team · Last updated: 2026-07-03
JSON Formatter is a free online tool that beautifies, indents, and validates JSON in your browser, turning a minified or messy string into clean, readable structure and flagging any syntax errors.
Why format JSON
Minified JSON from an API is a single dense line that is almost impossible to read. Formatting adds consistent indentation and line breaks so the structure becomes clear, making it easy to inspect a response, debug a payload, or understand a configuration file. Pretty-printing is one of the most common everyday tasks for developers working with web data.
Validation catches errors
Invalid JSON breaks parsers, and the usual culprits are a trailing comma, a missing quote, or an unbalanced bracket. The formatter validates as it parses, so it points out exactly where the syntax fails instead of leaving you to hunt. Confirming that a payload is valid JSON before sending it saves hours of debugging downstream.
Beautify and minify
Beautifying expands JSON with indentation for reading, while minifying strips all whitespace to make the smallest possible string for transmission. You typically beautify while developing and minify before sending data over the network, where every byte counts. Having both in one tool means you can switch between a readable view and a compact payload instantly.
Private and local
JSON Formatter runs entirely in your browser. Your JSON is parsed and formatted locally and is never uploaded or stored, so API keys, tokens, and private data inside the payload stay on your device. The processing is instant and no server sees your data.
사용 방법 JSON 포맷터
- Open the JSON Formatter tool.
- Paste your JSON into the input box.
- Choose to beautify or minify.
- Review the formatted output and any error messages.
- Copy the clean JSON to use anywhere.
Read an API response
Read an API response
Paste a minified API payload and beautify it to inspect the structure and values clearly.
Debug invalid JSON
Run a broken payload through the validator to find the exact spot where the syntax fails.
Minify before sending
Strip whitespace from a formatted object to produce the smallest payload for a request.
| Error | Example | Fix |
|---|---|---|
| Trailing comma | [1, 2, 3,] | Remove the last comma |
| Missing quote | {name: 1} | Quote the key |
| Unbalanced bracket | {"a": 1 | Close the brace |
관련 도구
주요 기능 JSON 포맷터
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