JavaScript Tools
Inar JavaScript Formatter
Inar JavaScript Formatter is a free online tool that formats, beautifies, and organizes JavaScript code instantly. Clean messy code, improve readability, adjust indentation, and format JavaScript directly in your browser with smart, easy-to-use options.
Inar JavaScript Formatter
Format, Beautify, Minify & Analyze JavaScript Online
A free online JavaScript formatter, beautifier and minifier with smart formatting,
syntax validation, code statistics and developer-friendly tools. Paste your code or
drop a .js, .mjs, .cjs or .json file —
everything is processed in your browser.
JavaScript Input
JavaScript Output Idle
Run Analyze or any formatting action to scan for console.log calls, debugger statements, TODO comments, empty blocks and other common issues.
Run a formatting operation, then click Compare input vs output to see what changed.
What is a JavaScript Formatter?
A tool that turns messy or minified JavaScript back into clean, readable, review-ready code.
A JavaScript formatter (sometimes called a JavaScript beautifier) rewrites source code with consistent indentation, spacing and line breaks so the structure of a program is easy to see at a glance. It changes how the code looks, not what it does — the same statements, expressions and values remain in place.
Minified JavaScript is small and fast to download, but it is almost impossible to read or debug. Formatting reverses that trade-off: the file grows in bytes but becomes far easier to review, hand over or learn from. It is the first step before making changes to a minified library, understanding an unfamiliar codebase, or reviewing a pull request.
Inar JavaScript Formatter runs entirely inside your browser. Your source code is never uploaded, never stored on a server and never shared with a third party. Nothing is evaluated — the formatter processes your JavaScript strictly as text.
Four Core JavaScript Tools
Each operation works on the raw text of your script — the tool never runs your code.
Format / Beautify
Rewrites JavaScript with your preferred indentation, brace style, spacing and quote rules, turning dense one-liners into readable, review-ready source.
Minify
Removes unnecessary whitespace and comments while preserving strings, template literals, regex literals and Automatic Semicolon Insertion boundaries.
Validate
Uses the browser's own parser to detect syntax errors, and reports the error message with an approximate line and column number.
Analyze
Reports code statistics plus common code-quality signals like console.log calls, debugger statements, TODO/FIXME comments and empty blocks.
Features
Everything you need to work with JavaScript in the browser — no installation, no account, no tracking.
Beautifier
Consistent indentation and spacing for classes, functions, objects and arrays.
Minifier
Safe whitespace and comment removal that respects strings, regex and ASI.
Validator
Detects syntax errors using the browser's own JavaScript parser.
Statistics
Lines, characters, functions, classes, comments and estimated minified size.
Find & Replace
Case-sensitive, whole-word and regex search with match counter.
Two editor modes
Single editor for in-place transformation, or split Input / Output view.
Before / After
Unified diff and side-by-side comparison for teaching and review.
File support
Upload or drag & drop .js, .mjs, .cjs and .json.
History
Recent operations are stored locally so you can restore earlier code.
Copy & Download
Copy to clipboard or download as formatted-script.js or minified-script.js.
Privacy first
100% client-side. Your code never leaves the browser.
Light & dark
A carefully tuned editor palette for both themes, saved locally.
How to Format JavaScript Online
Five quick steps from messy code to a clean, readable script.
Paste or upload your JavaScript
Paste your code into the input editor, drop a
.js,.mjs,.cjsor.jsonfile onto it, or use Examples to load a starting point.Pick your mode and options
Switch between Single editor and Input / Output, and open Options to set indentation, brace style, quotes, semicolons and comment handling.
Click Format
The beautified JavaScript appears instantly. Use Minify if you need a compressed production file instead.
Review diagnostics and analysis
The Diagnostics tab reports syntax errors with line numbers. The Code Analysis tab surfaces console.log calls, debugger statements, TODO comments and other signals.
Copy or download the result
Use Copy to place the code on your clipboard, or Download to save it as a
.jsfile. Keyboard shortcuts are available for both.
Formatting vs Minifying vs Validating
Three different jobs — pick the right one for the task at hand.
Formatting
Adds structure for humans. Indentation, line breaks and spacing make the code readable and reviewable. File size usually grows slightly because whitespace is added.
Minifying
Removes whitespace and comments to reduce the number of bytes the browser downloads. Strings, templates, regex literals and ASI boundaries are preserved.
Validating
Parses the code without executing it and reports syntax errors with a line and column number. It does not check logic, type correctness or runtime behaviour.
Frequently Asked Questions
Answers to the most common questions about the Inar JavaScript Formatter.
What is a JavaScript formatter?
A JavaScript formatter rewrites source code with consistent indentation, spacing and line breaks so the structure of the program is easy to read. It changes formatting only — not behavior.
What does a JavaScript beautifier do?
A beautifier is another name for a formatter. It takes compressed or inconsistently formatted JavaScript and expands it into a clean, readable layout with consistent indentation.
How do I format JavaScript online?
Paste your code into the input editor, choose your formatting options, then click Format. The beautified result appears in the output panel where you can copy or download it.
Can I format JavaScript without installing software?
Yes. Inar JavaScript Formatter runs entirely in the browser with no installation, account or extension required.
What is JavaScript minification?
Minification removes unnecessary whitespace and comments to reduce file size. It does not change what the code does — it only makes the file smaller for production.
Does minifying JavaScript change functionality?
Safe minification does not change behavior. This tool preserves strings, template literals, regex literals and Automatic Semicolon Insertion boundaries so the code keeps working exactly as before.
Can I validate JavaScript syntax?
Yes. The Validate button parses the code using the browser's built-in JavaScript engine and reports syntax errors with a line and column number. It does not execute the code.
Does Inar JavaScript Formatter store my code?
No. All processing happens locally in your browser. Your code is never uploaded to a server, an API or a third-party service. Only formatting preferences (theme, indentation, etc.) are stored locally.
Can I format Node.js JavaScript?
Yes. Node.js JavaScript — including require(), module.exports, and process usage — is formatted like any other JavaScript. There is no browser-specific restriction.
Can I format ES6+ JavaScript?
Yes. Modern syntax such as arrow functions, destructuring, template literals, classes, async/await, optional chaining and nullish coalescing is handled correctly.
Can I download formatted JavaScript?
Yes. Use the Download button to save the result as formatted-script.js or minified-script.js. If you uploaded a file, its base filename is preserved.
Can I use the JavaScript formatter on mobile?
Yes. On phones and tablets the input and output editors stack vertically, the toolbar wraps into readable rows and every action stays reachable. The page never scrolls horizontally.
More Inar Developer Tools
More free, privacy-friendly tools from Inar Learn — built for developers and learners.
Formatter Options
Formatting
Comments
License and legal comments beginning with /*! are always preserved during minification, even when other comments are removed.
Minification
Analysis preference
These preferences guide the analyzer's advice. The formatter never transpiles or rewrites syntax.
Editor
History
No history yet. Every formatting, minification or validation you run is stored locally in this browser.
Inar Learn