How to Format and Beautify JSON

Problem

Your JSON is a single long line and you need to make it readable for debugging or editing.

Prerequisites

• Understanding of JSON structure
• Familiarity with indentation

Steps

1. 1. Validate the input JSON

   Before formatting, confirm the input is valid JSON. If there are syntax errors (trailing commas, missing quotes), the formatter will fail. Fix any syntax issues first.

   Input

   {"name":"John","age":30,"city":"NYC"}

   Output

   valid JSON

2. 2. Apply indentation and line breaks

   Use a JSON formatter to add line breaks after each key-value pair and indent nested objects and arrays. A common indent size is 2 spaces. The formatter adds whitespace without changing the data.

   Input

   {"name":"John","age":30}

   Output

   {\n  "name": "John",\n  "age": 30\n}

3. 3. Review and use the formatted output

   Read through the formatted JSON to verify the structure. Proper indentation makes nested objects and arrays easy to follow. Copy the formatted JSON for editing or documentation.

   Input

   formatted JSON

   Output

   readable structure

Expected result

A valid, human-readable JSON string with consistent indentation and line breaks.

Common errors

Formatter fails with 'Unexpected token'

The input has a syntax error such as a trailing comma, single quotes, or a missing bracket. Fix the JSON before formatting.

Unicode characters become escape sequences

Some formatters escape non-ASCII by default. Use a formatter with an 'ensure ASCII false' option to keep Unicode readable.

Troubleshooting

• If the output looks wrong, validate the input JSON first.
• For very large JSON, use a streaming formatter to avoid memory issues.

Security limits

• Formatting JSON does not execute any code. However, do not trust JSON from untrusted sources without validation.