JSON Formatter & Validator
Paste your JSON to format, minify, or validate. Get pretty-printed output with 2-space indent, compact minified JSON, or check syntax with clear error messages and line numbers.
Use our Schema Markup Generator to create valid JSON-LD for SEO. Need custom APIs or data integrations? Our web development team builds robust backends with proper JSON handling and validation.
Explore All ToolsJSON Formatting and Validation
JSON (JavaScript Object Notation) is a lightweight data format used everywhere from APIs and config files to structured data for SEO. Valid JSON must use double quotes for strings, proper escaping for special characters, and correctly balanced braces and brackets. A JSON formatter helps you clean up messy or minified JSON so it's readable, while a validator catches syntax errors before they cause problems in your application.
When to Format vs. Minify
Formatting (pretty printing) adds indentation and line breaks to make JSON human-readable. Use it when inspecting API responses, debugging config files, or editing JSON by hand. Minifying removes unnecessary whitespace to reduce file size—ideal for production APIs, CDN delivery, or embedding JSON in HTML.
Common JSON Errors
Trailing commas after the last array element or object property are invalid in JSON. Single quotes are not allowed—use double quotes for strings. Unescaped newlines, tabs, or backslashes inside strings will cause parse errors. Keys must always be in double quotes. JavaScript undefined, NaN, and Infinity are not valid JSON values. Our validator reports the error message and approximate line number so you can fix issues quickly.
Related Developer Tools
- Schema Markup Generator — Create valid JSON-LD structured data for SEO
- On-Page SEO Checker — Audit your pages for search engine optimization
- Tech Stack Recommender — Get technology recommendations for your project
- Web Development Services — Custom APIs, data integrations, and JSON handling
Need API or Data Integration Help?
Working with complex JSON schemas, REST APIs, or data pipelines? Our web development team builds robust backends with proper validation, error handling, and type safety. Get in touch for a consultation.