Free Markdown Editor with Real-Time Preview — Japanese Supported
A browser-based Markdown editor optimized for Japanese IME input, with a live preview pane on the right as you type. Mermaid diagrams render inline. Export finished Markdown to HTML, PDF, or Word — perfect for internal docs, blog posts, and technical documentation.
What is Markdown and why use it?
Markdown is a lightweight markup language that uses simple symbols (# for headings, - for bullets, etc.) to represent formatting. It's easier to write than HTML and, because it's plain text, it version-controls cleanly with Git. Engineers widely use it for technical docs, blog posts, and READMEs.
Major platforms — Notion, GitHub, Slack, Qiita, Zenn — all support Markdown input, so content written once can be pasted anywhere.
Editor features
· **Real-time preview**: See the HTML rendering in the right pane as you type · **Mermaid support**: ` ```mermaid ` code fences render as live diagrams in the preview · **3 export formats**: HTML (styled) / PDF (WeasyPrint) / Word .docx (python-docx) · **"Clean up" function**: Fix irregular line breaks, mixed character widths, and extra spaces in one click · **Up to 200,000 characters** (enough for an entire book)
3 steps to use
1. Type Markdown in the left pane or upload a `.md` file 2. Check heading hierarchy, lists, tables, and Mermaid diagrams in the right preview pane 3. Click HTML / PDF / Word at the bottom to download in the format you need
IME (Japanese input) is handled without cursor drift. No lag even for long documents.
Why it's free and privacy
The Free plan is completely free and requires no account. Text is processed locally in the browser; it's only sent to our servers when you export (PDF/Word). Exported files are automatically deleted from S3 within one hour.
Safe to use even for documents containing confidential information.