Question 1

What does a JSON formatter actually do?

Accepted Answer

It takes a compact or poorly indented JSON string and reformats it with consistent indentation, line breaks, and spacing so the structure is easy to read. It also validates the input and reports any syntax errors.

Question 2

Is my data sent to a server when I format JSON?

Accepted Answer

No. Formatting runs entirely inside your browser using the built-in JSON.parse and JSON.stringify functions. Nothing you paste is ever transmitted anywhere.

Question 3

What does the sort keys option do?

Accepted Answer

When enabled, all object keys are sorted alphabetically at every level of nesting. This is useful for comparing two JSON objects or enforcing a consistent key order in configuration files.

Question 4

What indent style should I use?

Accepted Answer

Two spaces is the most common convention for JSON files and is the default in most code editors. Four spaces is common in some style guides. Tab indentation is used in certain codebases that prefer tabs. All three are valid JSON.

Question 5

Why does my JSON show as invalid?

Accepted Answer

JSON has strict syntax rules. Common mistakes include trailing commas after the last item in an array or object, single quotes instead of double quotes, unquoted keys, and comments (which are not allowed in standard JSON). The error message will point to the problematic location.

JSON Formatter

When to use this

Debug API responses

Validate JSON

Clean up configs

Free JSON formatter and validator

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