JSON Formatter / Validator
Format, validate, and minify JSON entirely in your browser. Syntax highlighting, line numbers, and instant error reporting.
Tips
JSON Has Strict Rules
Unlike JavaScript objects, JSON requires double-quoted keys, no trailing commas, and no comments. A single misplaced character can make the entire document invalid.
Indentation Affects Readability
2-space indent is common in web projects, 4-space in Python ecosystems, and tabs for personal preference. Choose what matches your team or project convention.
Minify for Transfer, Format for Reading
Minified JSON removes all whitespace, reducing file size by 20-40%. Use it for APIs and storage. Switch to formatted view when debugging or reviewing data.
Validate Before You Ship
Pasting JSON into config files or API requests without validation is a common source of bugs. A quick format-and-validate check catches issues before they reach production.
Common Use Cases
API Response Inspection
Paste raw API responses to format and validate them. Quickly spot missing fields, wrong types, or structural issues.
Config File Editing
Format package.json, tsconfig.json, or other config files for easier reading and editing.
Log Data Analysis
Format JSON log entries to make nested structures readable. Identify patterns in error logs or event streams.
Frontend Development
Validate mock data, API schemas, or i18n translation files before integrating them into your application.
Data Transformation Check
After converting CSV, XML, or YAML to JSON, validate the output to ensure the conversion was correct.
Documentation
Format JSON examples for technical documentation, tutorials, or README files with consistent indentation.