About this tool
Pretty-print, validate, and minify raw JSON payloads with instant error line highlighting, character counts, and zero server roundtrips.
JSON Formatter
Format, validate, and minify JSON with real-time syntax error line highlighting and tree inspection.
Example
- json: {"name":"LilUtils","active":true}
- format: pretty
- indent: 2
Output
DEVWaiting
Run the tool to generate output.
When to use this tool
Use JSON Formatter when debugging API endpoints, reviewing configuration files, or cleaning up minified data payloads before sharing.
Inputs, Formats & Specifications
- Accepted Inputs
- Raw JSON string, minified JSON, or JavaScript object notation
- Output Formats
- Beautified 2-space/4-space formatted JSON, minified single-line string, syntax validation report
- Supported Standards
- Standard JSON (RFC 8259)
- Browser Limits & Scope
- Follows strict RFC 8259 JSON standards (comments and unquoted keys are invalid in standard JSON). Handles files up to browser memory limits (~50 MB).
How to use this tool
- Paste raw, unformatted, or minified JSON text into the code input editor.
- Click 'Format JSON' to immediately beautify the payload with standard 2-space or 4-space indentation.
- If a syntax error exists, inspect the highlighted line and column indicator explaining the exact parsing failure.
- Copy the formatted JSON, minify it to a single line, or download it as a `.json` file.
Examples
API Payload Debugging
Format a dense, minified JSON response from a REST or GraphQL API to inspect nested arrays, object keys, and null values.
Config File Validation
Validate a `package.json`, `tsconfig.json`, or Kubernetes config snippet before committing to ensure there are no trailing commas or missing quotation marks.