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            Language
            
            Theme
            
            Open a file from your device

Click Launch editor to load the in-browser editor (one-time download, runs entirely on your device).

            Snippet name
            
            Load a saved snippet

Snippets are stored only in this browser (localStorage). Nothing is uploaded.

Code Editor

Last reviewed: 2026-06-16

Click Launch editor to open a full code editor in your browser - the same Monaco engine that powers VS Code. Pick from 18 languages and a light, dark, or high-contrast theme, then write or edit code with syntax highlighting, a minimap, code folding, and bracket matching.

Key features

Code editor features: 18 languages, three themes, VS Code conveniences including code folding and word wrap, and open-and-save files in the browser. — Four key features of the Monaco-powered in-browser code editor.

18 languages - JavaScript, TypeScript, Python, Java, C#, C++, Go, Rust, SQL, HTML, CSS, JSON, and more.
Light, dark, and high-contrast themes - switch either the language or the theme at any time.
VS Code conveniences - minimap, code folding, bracket matching, word wrap, line numbers, and format-on-paste.
Open and save files - open a file from your device to edit it, then save your work back to a file or download it.
Named snippets - save snippets that persist in this browser so you can reload them later, no account required.

When to use it

Handy on a machine without your usual editor - a shared review laptop, a client device, or a phone. Open the file, edit it with full syntax highlighting, then save or download it; save a named snippet to resume later.

Save options by browser

Browser	What "Save / Download" does
Chromium (Chrome, Edge, Brave)	Writes to a file you choose, using the File System Access API.
Firefox, Safari	Downloads the file - the universal fallback everywhere else.

The file extension is picked automatically from the language you are editing.

Your code stays on your device

The Monaco engine is self-hosted, so it downloads once on Launch, then makes zero network requests for your code - nothing is uploaded and there is no backend. Your named snippets live only in this browser's local storage: they reload instantly when you come back, but they do not sync across devices and clearing site data removes them. And because this is an editor, not a sandbox, your code is yours to draft, format, and save - it never runs here, so paste a work-in-progress without worrying it will execute.

The editor runs on your device; your code is never uploaded.

This is one of the developer tools. When a script is ready to ship, shrink it with the JS Minifier, or browse the full set of formatters, minifiers, and converters on the hub.

Read the guide: How to Edit Code Online - Free, In Your Browser

Last reviewed: 2026-06-16

FreetoolOnline editorial team

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Last updated: Jul 8, 2026

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Tags: #developer

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Frequently Asked Questions

What does Code Editor do?

Edit a code directly in the browser without installing anything.

When should I reach for code editor?

Export the edited result when you are done.

What complementary tools work well alongside code editor?

For format conversion before or after editing, see the related-tools section.