JSON Formatter and Validator

JSON beautifier online

Readable JSON helps you inspect API responses, configuration and sample payloads. This formatter parses your input and presents either an indented version or a compact version. If the input contains invalid syntax, it reports the parsing error so you can correct the text before exporting it. Formatting does not validate a business schema or required application fields.

How to use it

Paste JSON, select pretty print or minify, choose an indentation size and run the formatter. Copy the result or download a JSON file.

Options and example settings

Worked examples

Inspect an API response or configuration value. Parsing confirms JSON syntax; formatting changes presentation and can change number precision or duplicate keys.

Format an object

Settings: Pretty print; indentation: 2 spaces

Input:

{"name":"Kirikuba","active":true}

Each field appears on its own indented line.

Output:

{
  "name": "Kirikuba",
  "active": true
}

For this input, “active” is true. These are the named fields in the example output.

Keep a large identifier as text

Settings: Pretty print; indentation: 2 spaces

Input:

{"id":"9007199254740993"}

The quoted identifier remains exact.

Output:

{
  "id": "9007199254740993"
}

The example returns an object with 1 top-level field. The fields “id” identify the returned values or sections.

Minify valid JSON

Settings: Minify

Input:

{
  "a": 1,
  "b": [true, null]
}

Insignificant whitespace is removed.

Output:

{"a":1,"b":[true,null]}

For this input, “a” is 1. These are the named fields in the example output.

Choose the right tool

Choose this tool to check JSON syntax or change its layout. JSON Schema Validator checks a supplied schema, JSON Comparison finds changed values, and JSON Tree Viewer helps explore nested data.

Limitations and common mistakes

• JSON property names and string values require double quotes. Single-quoted JavaScript objects are not JSON.
• Remove trailing commas and comments. The formatter reports errors; it does not automatically repair them.
• Keep large integer identifiers in strings. JavaScript number parsing can round values outside its safe integer range.
• Repeated object keys keep the last value when parsed. Formatting cannot recover overwritten entries.
• Dates remain strings; formatting does not validate their calendar meaning.
• JSON syntax validity does not prove schema validity; large numeric identifiers can lose precision.

Frequently asked questions

Does valid syntax mean my API payload is correct?

No. Syntax validation does not check required fields, allowed values, types or your application rules. Use JSON Schema Validator when you have a schema.

Does it support JSON5 or comments?

No. Input must use standard JSON syntax; comments and trailing commas are rejected.

Can formatting change my data?

Yes. JavaScript numeric precision and repeated object keys can affect parsed values. Quote identifiers that must remain exact and check for duplicate keys before formatting.

How can I pretty print JSON online?

Paste JSON, select pretty print or minify, choose an indentation size and run the formatter. Copy the result or download a JSON file.

Technical references

• MDN: JSON.parse

Where is my input processed?

The bundled tool processes input in your browser. It does not upload tool input to a conversion service. Other site plugins, analytics, advertising and browser extensions may have separate behavior.

Useful next tools

• JSON Unescape and Escape
• JSON Comparison
• JSON Schema Validator
• CSV to JSON and JSON to CSV Converter