Tool workspace

JSON Formatter

Clean up messy JSON or compress it for transport with one click.

Runs locally in your browser.

Review important security-sensitive data and configurations independently.

Indentation

JSON input

Output

Use in code

Format JSON for readability with indentation, or serialize compact JSON for transport.

Pretty-print JSON

TypeScript

Primary API

JSON.stringify(value, null, 2)

Serializes objects into readable JSON with two-space indentation.

Built-in APILibrary: JSON

const data = { user: { id: 1, roles: ["admin", "editor"] } };

const formatted = JSON.stringify(data, null, 2);
console.log(formatted);

Reference: JSON documentation

How to use

Paste JSON into the input area.
Choose indent size, then click Format or Minify.
Copy the output or clear to start over.

Use cases

Inspect API responses during development and debugging.
Prepare readable JSON for code reviews and documentation.
Minify JSON before embedding it in config files or payloads.

Examples

Before: {"user":{"id":1,"roles":["admin","editor"]}}
After format: each object and array appears on separate indented lines.
After minify: whitespace is removed to reduce payload size.

Limitations and caveats

Input must be valid JSON syntax before it can be formatted.
Formatting does not validate business rules or schema requirements.

History

JSON was introduced in the early 2000s as a lightweight data-interchange format inspired by JavaScript object notation.
It gained broad adoption as REST APIs and browser applications expanded, replacing heavier XML workflows in many projects.
As JSON payloads became larger and nested, dedicated formatter tools became standard for debugging and code review.

Source: RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format · JSON.org overview

Evolution and improvements

Early formatters focused on indentation only; modern tools now include minify, copy, and error feedback workflows.
Developer tooling evolved from command-line scripts to instant browser-based formatters for quick checks.
Today, formatting is often paired with validation and schema checks in CI and local development pipelines.

Source: RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format · JSON.org overview

FAQ

What does JSON formatting actually do?

Formatting rearranges whitespace and indentation to improve readability without changing values.

Formatting vs minifying: what is the difference?

Formatting makes JSON easier to read. Minifying removes extra spaces and line breaks to shrink size.

Why am I seeing an error instead of formatted output?

The input likely has syntax issues such as trailing commas, missing quotes, or unmatched braces.

Does this send my JSON to a server?

No. Processing happens in your browser.