Kotlin Formatter
Format and beautify Kotlin code with consistent indentation and clean structure
Kotlin Formatting Tips
- Use 4-space indentation as recommended by the Kotlin coding conventions.
- Place opening braces on the same line for functions and classes.
- Use trailing commas in multi-line collections and parameter lists for cleaner diffs.
Professional Kotlin Formatter Processing Features
Everything you need to work with Kotlin Formatter data efficiently and professionally
Syntax Validation
Detect unclosed braces, brackets, and parentheses with precise error reporting for Kotlin code.
Beautify Kotlin Code
Transform messy Kotlin code into clean, consistently indented code following Kotlin coding conventions.
DSL Formatting
Properly format DSL builders, scope functions, and trailing lambda expressions with clean indentation.
Composable Support
Correctly format Jetpack Compose composable functions with nested modifiers and layouts.
Fast Processing
Format Kotlin files up to 10MB instantly with client-side processing, no server round-trips needed.
Smart Indentation
Intelligent indentation for data classes, sealed classes, objects, and extension functions.
How It Works
Simple steps to process your Kotlin Formatter like a pro
Paste Your Kotlin Code
Paste your Kotlin source code into the input area, or load a sample to get started.
Customize Options
Choose indentation size to match your project conventions.
Format & Review
Click the format button to beautify your Kotlin code and review the clean output.
Copy or Download
Copy the formatted code to your clipboard or download it as a file for your project.
Professional Kotlin Formatter Formatter & Validator
Kotlin Formatter processing runs entirely in your browser — no uploads, no accounts, no limits.
Processing method
Use this tool’s examples, syntax limits and source documentation to understand its output.
Key Technical Features:
- • Kotlin syntax-aware parsing with brace matching
- • Support for Kotlin 2.0 features including context parameters
- • Intelligent indentation for DSL blocks and scope functions
- • Client-side processing for maximum security and speed
- • Support for large files up to 10MB
Processing and output
Check the stated processing method and compare the result with your input before using it.
Security & Privacy:
- • 100% client-side processing - data never sent to servers
- • No tracking, cookies or data collection
- • HTTPS encryption for secure connections
- • No data stored or cached after processing
- • GDPR and CCPA compliant approach
Why Professionals Choose EZ Formatter
Your data stays in your browser
Frequently Asked Questions
Common questions about Kotlin Formatter formatting answered
Yes, our Kotlin formatter is completely free with no registration required. All processing happens in your browser.
Yes, our formatter properly handles Jetpack Compose composable functions with consistent indentation.
Yes, it correctly formats coroutine builders, suspend functions, and Flow chains with proper indentation.
No. The formatter only adjusts whitespace and indentation. It never modifies identifiers, types, or logic.
It follows the official Kotlin coding conventions with 4-space indentation and consistent brace placement.
The official Kotlin Coding Conventions (kotlinlang.org): 4-space indent, no wildcard imports (the IDE's Kotlin style bans them where Java's permits up to a threshold), and constant naming in SCREAMING_SNAKE or camelCase per the companion-object rule. Jetbrains' ktlint and the IntelliJ formatter follow the same document.
Function expression bodies (fun double(x: Int) = x * 2) stay on one line when they fit, with = spacing exact; when expressions break one branch per line with -> aligned in consecutive arms. Since Kotlin 1.4, comma-before-when-branch (multi-label cases) is used and preserved.
String templates ("$name is ${age + 1}") are never re-spaced inside the braces - they are expressions. The safe-call chain (user?.profile?.name ?: "default") keeps its operator adjacency (?. and ?: are tight), and !! stays glued to its operand; only the surrounding statement layout changes.
Authoritative References
Standards and official documentation that define the formats this tool works with.
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