A Free Online Code Editor With Live Preview — No Signup Required
Most free online code editors stop at HTML, CSS and JavaScript, and even then the preview only updates after you press a button. The HB Tools Online Code Editor was built to fix both of those limits at once. Type in the HTML, CSS or JS tab and the preview updates itself a moment later — no Run button needed. Beyond the browser trio, it also lets you run Python code online in your browser, use it as a SQL editor online with no installation needed, and even try it as a PHP online compiler with no signup required. On top of that, in Chrome and Edge, it doubles as a browser based code editor that opens local folders straight from your computer, so you can create, rename, move and delete real files the way you would in a lightweight desktop IDE.
If you're testing a small script, walking someone through the basics of a language, checking a SQL query without spinning up a database server, or working across a handful of files in a real project folder, this tool is meant to get you from idea to output in seconds — not minutes. It's also a handy option for anyone who wants a free code playground without creating an account, installing an IDE, or configuring a local dev environment first.
A Live Preview Code Editor That Updates As You Type
Switch to the HTML, CSS or JS tab and just start typing. With Auto-run switched on by default, the preview pane refreshes a short moment after you pause — no clicking Run every time you tweak a line. This makes cause-and-effect obvious for beginners: change a CSS value, and the layout shifts immediately in front of you. If you'd rather control it manually, turn Auto-run off in the toolbar, and the preview will only update when you click Run or press Ctrl/Cmd + Enter. Any JavaScript errors are caught and shown right in the status bar, so you don't have to dig through a separate console tab to spot a typo.
A Browser Based Code Editor That Opens Local Project Folders
Click the folder icon in the sidebar and, in Chrome, Edge or another Chromium-based browser, pick any folder on your device. The editor reads it into a file tree you can browse and expand, click any file to open it in a new tab, create new files and folders anywhere inside it, rename any file or folder in place, drag and drop items between folders, hold Ctrl/Cmd and click to multi-select for a bulk delete, and jump to any file instantly with Ctrl/Cmd+P. All of this runs on the browser's own File System Access API, so nothing from your project folder is ever uploaded anywhere — it's a genuinely local file explorer, not a cloud sync. The editor also remembers your last opened folder and offers to reopen it the next time you visit, and pressing Ctrl/Cmd + S while editing a file saves straight back to disk. Safari and Firefox don't support this API yet, so on those browsers the sidebar shows a short note while the six built-in playground tabs stay fully usable.
Work Across Multiple Files Without Losing Your Place
Every file you open — from a folder or individually — gets its own tab next to the built-in HTML, CSS, JS, Python, SQL and PHP tabs, with a breadcrumb underneath showing exactly where it lives in your project. A small dot marks a tab with unsaved changes, so you always know what still needs saving. Close a file tab with the × once you're done; the six default playground tabs always stay available as a quick scratchpad, and their contents auto-save locally so a refresh or crash won't cost you your work.
Format, Search and Navigate Like a Real Editor
Press Ctrl/Cmd+Shift+F to auto-format HTML, CSS, JavaScript or JSON in one click — a built-in code beautifier so you don't need to paste your code into a separate formatting tool. Press F1 for the editor's command palette, or F2 to rename the selected file or folder in place. Ctrl/Cmd+P opens a fuzzy quick-open box so you can jump to any file in your project just by typing part of its name — a small touch that saves a lot of scrolling once a project grows past a handful of files. And if you're on a mobile browser where curly braces and quotes are buried behind extra keyboard taps, a symbol bar above the editor gives one-tap access to the characters you type most often.
Run Python Code Online in Browser — Plus SQL and PHP, No Installation Needed
The Python tab runs on Pyodide, so you can run Python code online in your browser without installing anything on your machine. The SQL tab works as a SQL editor online with no installation needed, running an in-memory SQLite database via sql.js — perfect for testing a query before it touches a real database. And the PHP tab acts as a PHP online compiler with no signup required, running through php-wasm. All three are real interpreters compiled to WebAssembly and loaded directly into your browser tab the first time you use them. Print statements, query results and errors all show up in the console panel, and it works the same whether you're using the default playground tabs or a Python, SQL or PHP file opened from your own folder. There's no server-side execution queue to wait on, since everything runs locally on your own device the moment you hit Run.
Works on Desktop and Mobile, With Sensible Fallbacks
The editor is fully usable on a phone or tablet browser for writing and running code in any of the six supported languages — the layout adapts to a single column, and the toolbar collapses into a scrollable strip. The local folder explorer is the one feature that needs the File System Access API, which today is only available in desktop Chromium browsers, so that panel is hidden with a short explanation on unsupported browsers rather than breaking silently. Everywhere else — auto-run, formatting, theme switching, ZIP export — works identically across devices and browsers, so you're never stuck without a working editor.
100% Private — Your Code Never Leaves Your Device
Running your code never touches a server. HTML, CSS and JavaScript render locally in a sandboxed iframe, Python, SQL and PHP execute inside WebAssembly runtimes right in your browser, and opened folders are read and written directly through your browser's own file system permission. HB Tools never uploads their contents anywhere — nothing about your code or your files is ever sent to a server. That also means there's no daily usage cap, no rate limit, and no account tied to what you write.
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