About the JSON Formatter
Overview
JSON (JavaScript Object Notation) is a common data format for APIs and configuration. This tool formats (pretty-prints) or minifies JSON so you can read it easily or reduce size. Formatting adds indentation and line breaks; minifying removes unnecessary whitespace and can shrink payloads for production. Validation happens automatically: invalid JSON is reported with an error message so you can fix syntax before using the data.
Many APIs and config files use JSON. The JSON to XML Converter helps when you need to convert between JSON and XML. For structured data in web pages, the Schema.org tool generates and validates JSON-LD.
When to use it
Use the formatter when you receive minified JSON from an API or file and want to inspect it. Use minify when you need to embed JSON in HTML or send it in a request with minimal size. Use it to validate pasted JSON before putting it into code or a database. When working with XML systems, combine with the JSON to XML Converter; for SEO structured data, use the Schema.org generator and validator.
How to use it
Paste your JSON into the input area. Click Format to pretty-print with indentation; click Minify to remove extra spaces and newlines. The output appears in the result box. Use Copy to copy the result to the clipboard. If the input is invalid (e.g. trailing comma, missing quote), an error message appears and the output is not updated until the JSON is valid. Clear clears both input and output so you can start fresh.
Tips
Always validate JSON from external sources before using it in production. Trailing commas and single quotes are invalid in standard JSON; fix them before formatting. For very large JSON (megabytes), consider splitting or processing in chunks to avoid browser limits. When building APIs, return minified JSON by default and offer optional pretty-print via a query parameter. The Schema.org tool validates JSON-LD specifically for structured data.
Common mistakes
Trailing commas after the last array element or object property cause parse errors in strict JSON. Unescaped newlines or quotes inside strings break parsing. Comments are not allowed in JSON; remove // or /* */ before formatting. Copying only part of a response (e.g. missing closing brace) produces invalid JSON. Ensure the entire document is selected when pasting from logs or network tabs.