Free JSON Formatter & Beautifier
Format, beautify and validate JSON with configurable indentation
JSON Formatter Features
Everything you need to work with JSON data
Beautify JSON with 2 spaces, 4 spaces or tab indentation in one click.
Detects and reports JSON syntax errors with the exact position of the problem.
Remove all whitespace and produce compact JSON ready for APIs and storage.
About the JSON Formatter
Our free JSON formatter makes unreadable minified JSON easy to inspect and debug. It validates syntax, highlights errors and supports three indentation styles for any workflow.
Frequently Asked Questions
Why format JSON?
JSON returned by APIs is often minified with no whitespace to reduce transfer size. While efficient for machines, it is nearly impossible for humans to read.
Formatting adds indentation that reveals the structure: which keys belong to which objects, which items are in arrays and how deeply nested the data is.
This makes debugging API responses, config files and data exports much faster.
What causes JSON validation errors?
Common causes include missing quotes around keys, trailing commas after the last item in an array or object, single quotes instead of double quotes, and comments which are not valid in JSON.
Other errors include unescaped special characters in strings and incorrect nesting of brackets or braces.
Our tool displays the exact error message from the JavaScript parser to help you locate and fix the problem quickly.
When should I use 2 spaces versus 4 spaces?
Two space indentation is compact and fits more content on screen. It is popular in JavaScript projects and many code style guides including Airbnb and Google.
Four space indentation provides more visual separation between levels and is preferred in Python, Java and some older JavaScript conventions.
Tab indentation lets each developer adjust the visual width in their own editor, which is why some teams prefer it for shared codebases.
What is the difference between formatting and minifying?
Formatting adds whitespace and newlines to make JSON readable. Minifying removes all non-essential whitespace to make JSON as compact as possible.
Minified JSON is used in production APIs, configuration files and anywhere where file size matters. Formatted JSON is used for debugging, documentation and human review.
Both operations preserve the exact same data. Only the whitespace changes, not the values.
Can this tool handle nested JSON?
Yes. The tool handles any valid JSON including deeply nested objects and arrays of any complexity.
Deeply nested structures benefit most from proper formatting because the indentation levels visually communicate the hierarchy.
There is no nesting depth limit in the tool beyond what the JavaScript engine can handle.
Does formatting change the data?
No. Formatting only adds whitespace characters between tokens. The actual data values, keys and structure remain completely unchanged.
However, key order within objects may change because JavaScript objects do not guarantee insertion order. In practice most JSON parsers preserve order for non-integer keys.
If key order matters for your use case, verify the output against your original.
What JSON data types are supported?
All standard JSON data types are supported: strings, numbers, booleans (true/false), null, objects and arrays.
Dates are not a native JSON type. They are typically represented as ISO 8601 date strings like "2024-01-15T10:30:00Z".
Special number values like Infinity and NaN are not valid JSON and will cause a validation error.
Are there any file size limits?
There is no hard limit. Processing happens in your browser using native JavaScript which is very efficient for JSON parsing.
Very large JSON files of several megabytes may take a moment to format and the output textarea may become slow to scroll, but the formatting itself will succeed.
For files larger than 10 MB consider using a dedicated desktop JSON editor for better performance.