Format JSON and find syntax errors before copying it

Step by step

1. Copy the JSON body, not HTTP headers or a JavaScript variable assignment. Keep the original if it contains important data.
2. Choose Format (2-space indent), paste the input and run the tool. Nested objects and arrays appear on separate lines.
3. For a syntax check, choose Validate only. A trailing comma or an unquoted property name must be corrected; the tool does not repair it automatically.
4. Use Minify to one line only when compact output is needed. Copy the result and check it against the receiving application's field requirements.

A worked example

Checked using the local JSON Formatter in a browser with the sample below.

Input

{"name":"Vubilo","items":[1,2],"active":true}

Setting

Format · 2-space indentation

Observed

3 top-level keys; items contains 2 values; active remains true

This small example verifies the displayed formatting only. It does not test large documents, schema compliance or arbitrary-precision numbers.

Try a small response first

Use {"name":"Vubilo","items":[1,2],"active":true}. Formatting expands the two array items and keeps the boolean as true. Whitespace is presentation; it is not a change to the intended values.

Try {"name":"Vubilo",} to see a syntax error, then remove the final comma. Do not convert all quotes by blind replacement: apostrophes may be legitimate text inside strings.

What this check cannot guarantee

The implementation parses JSON using JavaScript numbers. Very large integers can lose precision; represent identifiers as quoted strings before using this tool. Duplicate object keys can collapse to the last value. Keep the original when either matters.

Validation checks JSON syntax, not business rules, required API fields or a JSON Schema. Avoid pasting secrets into shared devices, and do not assume formatted output is a lossless archive of the original text.

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