JSON Formatter & Validator
Paste your JSON below, then format it into readable, indented output or minify it down to a single line. Invalid JSON is flagged immediately.
What this tool does
The JSON formatter and validator checks whether the JSON you paste is syntactically correct, then lets you pretty-print it with two-space indentation for readability or minify it to a compact single line for transport. Parsing happens entirely in your browser using the native JSON parser, so your data is never sent to a server.
Example use case
Developers debugging an API response often receive a JSON payload as an unreadable single-line string in logs or browser dev tools. Pasting it here instantly reformats it into an indented, human-readable structure, making it easy to spot missing fields or unexpected nesting. Conversely, when preparing a JSON config file or request body for production, minifying removes unnecessary whitespace to reduce payload size.
Common errors it catches
Trailing commas, unquoted property names, single quotes instead of double quotes, and mismatched brackets are among the most common JSON mistakes. When your input is invalid, the tool reports the specific parsing error so you can find and fix the problem quickly instead of scanning the whole document by hand.