Does this send my code anywhere?

No. Reindenting runs entirely in your browser.

Why not use a real Java formatter like google-java-format?

google-java-format and similar tools require a JVM to run, which isn't available in a browser. This tool instead reindents by tracking brace nesting depth, which fixes the most common formatting drift without needing Java installed.

What indent size does it use?

A fixed 4 spaces per nesting level. Note that Google's own style guide specifies 2-space indentation, so if you need output matching google-java-format's default, run that locally rather than relying on this tool's width.

Does it understand annotations like @Override or @SuppressWarnings?

Not specially. Annotation lines are scanned like any other line, so parentheses inside an annotation's arguments, like @SuppressWarnings("unchecked"), are counted toward nesting depth the same way a method call's parentheses would be.

Java Formatter - Format Java Online

Overview

Introduction

Java code pasted from different IDEs or after manual edits often has indentation that no longer matches its brace structure.

This tool reindents each line based on `{ }` nesting depth, entirely in your browser, without requiring a JVM.

What Is Java Formatter?

A lightweight reindenter that tracks brace, parenthesis, and bracket depth line by line and re-indents accordingly.

It's a whitespace-only pass: tokens, strings, and logic are never touched, only leading indentation.

How Java Formatter Works

Each line is scanned for `{}/()/[]` characters to compute a running nesting depth.

Lines that start with a closing brace are dedented one level before printing, matching their opening brace.

When To Use Java Formatter

Use it when a Java snippet's indentation has drifted after edits or a copy-paste from a non-IDE source.

It's a quick visual check that braces are balanced.

Often used alongside C Formatter, Go Formatter and Rust Formatter.

Features

Advantages

Runs entirely client-side with no JVM required.
Fixes indentation drift instantly for typical brace-delimited code.
Handles arbitrarily deep nesting without any configuration needed.

Limitations

Not a real parser: brace characters inside string literals or comments still affect depth.
For rigorous style enforcement, use google-java-format or your IDE's formatter locally.

Examples

Drifted indentation

Input

public class Greeter {
public String greet(String name) {
return "Hello, " + name;
}
}

Output

public class Greeter {
    public String greet(String name) {
        return "Hello, " + name;
    }
}

Each closing brace dedents to match its opener, and nested content indents one level deeper per `{`.

Best Practices & Notes

Best Practices

Use this for a quick cleanup pass, then run your IDE's formatter or google-java-format before committing.
Check whether the final line's indentation returns to depth zero, that's a quick sign no closing brace is missing.

Developer Notes

Implemented as a single-pass line scanner that tracks a running brace/paren/bracket balance; it does not tokenize strings or comments.

Java Formatter Use Cases

Quickly cleaning up indentation in a pasted Java snippet
Spotting an unbalanced brace by eye before pasting into an IDE

Common Mistakes

Relying on this for production formatting instead of a real Java-aware tool like google-java-format.
Assuming brace characters inside string literals or comments are ignored, they aren't; the scanner counts every `{`, `}`, `(`, `)`, `[`, or `]` regardless of context.

Tips

If output looks wrong, check for a string literal or comment containing an unmatched brace character.
Diff the reindented output against your original before committing it, so you can see exactly which lines shifted.

Java Formatter