Java Formatter & Beautifier - Format Java Code Online

What Is a Java Formatter?

A Java formatter rewrites the whitespace in a source file so its structure is visible at a glance. Blocks are indented by their nesting depth, operators and commas get consistent spacing, opening braces sit at the end of the line that introduces them, and runs of blank lines are collapsed. What it never does is change your program: no statement is reordered, nothing is renamed, no logic is touched. Compile the input and the output and you get the same bytecode.

What This Formatter Changes

• Rebuilds indentation at four spaces per level, from the real brace structure
• Puts case and default one level inside the switch, and their statements one level further in
• Adds spaces around assignment, comparison, logical and arithmetic operators
• Normalises commas and semicolons: none before, one space after
• Writes if (…) { rather than if(…){, while leaving method calls like foo(x) tight
• Indents lines that continue an unclosed parenthesis
• Collapses multiple blank lines to one and ends the file with a single newline

What It Deliberately Leaves Alone

A formatter that quietly corrupts your data is worse than no formatter, so this one is conservative in three specific ways.

• Literals and comments are untouched. The inside of a string, a character literal, a text block or a comment is copied byte for byte. A comma inside "a, b" is not a list separator and is never treated as one.
• Text blocks keep their indentation. In a Java text block the leading whitespace is part of the string value, so re-indenting it would change your data. Those lines are emitted exactly as written.
• Angle brackets are left as-is. a<b and List<String> are indistinguishable without full type information. Adding spaces would break generics, so comparisons stay unspaced — a small cosmetic cost for a guarantee that nothing is mangled.

Before and After

public class Greeter {
private String name;
public void greet(List<String> p){
for(int i=0;i<p.size();i++){
System.out.println("Hi, "+p.get(i));
}
}
}

public class Greeter {
    private String name;
    public void greet(List<String> p) {
        for (int i = 0; i<p.size(); i++) {
            System.out.println("Hi, " + p.get(i));
        }
    }
}

Who Uses a Java Formatter

Formatting Is Idempotent

Running the formatter on its own output produces exactly the same text. That property matters more than it sounds: it means the tool has a single fixed idea of correct layout, so repeated use never drifts, and formatted code checked into version control will not produce a spurious diff the next time somebody formats it.

Privacy and Limits

Formatting runs on our servers, not in your browser: your source is sent over HTTPS, formatted, and returned. It is never shared with third parties or used for advertising. Even so, treat it as an upload — do not paste API keys, credentials, or proprietary code you are not permitted to transmit. Source files are capped at 2 MB.

This is a formatter, not a compiler. It will lay out code that does not compile and will not report syntax errors. Working with database code too? The SQL formatter applies the same approach to queries, and JSON to Java POJO generates classes from an API response.