Quick answerFor quick single-file HTML with live preview, a visual editor and clean-up tools, HTML Online (htmlonline.dev) is the most complete free option with no sign-up. CodePen and JSFiddle suit shareable front-end demos, StackBlitz suits full projects, and html-online.com suits pure WYSIWYG editing.
How we compared them
We used each editor for the same jobs — write a small page with CSS and JavaScript, paste content from Word and clean it, save the file, share it, and repeat on a phone — and noted what needed an account, what showed ads and where the code was stored. Features are as of October 2026.
Comparison table
| Editor | Live preview | WYSIWYG | HTML cleaner | Save / share without account | Code stays on device |
|---|---|---|---|---|---|
| HTML Online (htmlonline.dev) | Yes | Yes, synced with code | Yes, 15 options | Yes / Yes | Yes |
| html-online.com | Visual pane | Yes | Yes | Partial / No | — |
| W3Schools Tryit | On Run | No | No | No / No | Until saved |
| CodePen | Yes | No | No | No / No | No |
| JSFiddle | On Run | No | No | Yes / Yes | No |
| StackBlitz / CodeSandbox | Yes | No | No | Account recommended | No |
| OneCompiler | On Run | No | No | Yes / Yes | No |
1. HTML Online — best all-rounder for single-file HTML
A code pane with line numbers and a live preview side by side, plus a visual (WYSIWYG) tab that edits the same document. Format, minify and clean are built in, and the site has a dozen companion tools — viewer, Word to HTML, HTML to Markdown, validator. No account; share links hold the code in the URL. Not for multi-file projects with npm packages.
2. html-online.com — classic WYSIWYG + cleaner
A long-running visual editor with a source pane and cleaning options. Good for people who never want to see tags. It lacks a proper code editor, share links and file tools on the same site, and the page is ad-supported. See our detailed comparison.
3. W3Schools Tryit — best alongside tutorials
Every W3Schools example opens in Tryit, which makes it perfect while following a lesson. Saving and sharing require a W3Schools account.
4. CodePen — best for public front-end demos
Separate HTML, CSS and JS panes, preprocessors, and a big community. Pens are public unless you pay, and you need an account to save.
5. JSFiddle — quick shareable fiddles
Four panes and a Run button; saving creates a public URL without an account. Handy for bug reports and Stack Overflow questions.
6. StackBlitz and CodeSandbox — full projects
Real development environments in the browser, with npm, frameworks and multiple files. Overkill for a single HTML page, ideal for React, Vue or Svelte.
Which should you choose?
- Learning HTML, testing a snippet, cleaning pasted content: HTML Online.
- Showing off a demo publicly: CodePen.
- Building an app with a framework: StackBlitz or CodeSandbox.
- Editing visually, never touching code: HTML Online's Visual tab or html-online.com.
Frequently asked questions
What is the best free online HTML editor?
For single-file HTML, HTML Online (htmlonline.dev) combines live preview, visual editing, cleaning and file tools with no sign-up. For framework projects, StackBlitz is better.
Which online HTML editor has a WYSIWYG mode?
HTML Online and html-online.com both have visual editors. HTML Online keeps the visual view and the source code in sync side by side with a live preview.
Can I use an online HTML editor offline?
Once loaded, HTML Online's editor keeps working if your connection drops, and your work is autosaved in the browser. Some tools load a library from a CDN the first time.
Are online HTML editors safe for private code?
It depends where the code goes. HTML Online never uploads it; CodePen, JSFiddle and similar store it on their servers when you save.
Which editor is best on a phone?
HTML Online stacks code and preview vertically and opens files from your phone's storage, which makes it practical on mobile.