Markdown Preview – 即時編輯與預覽

帶即時編輯器的 Markdown 預覽：輸入 Markdown，立即查看渲染的 HTML。複製或下載結果。離線可用。

Write Markdown on the left, watch it render on the right — instantly, as you type. Markdown Preview is a live Markdown editor and a Markdown preview tool in one window. Open the popup, start typing, and the preview updates with every keystroke. Or paste Markdown you already have and read it rendered. No file to open first, no upload, no account. WHAT IT IS FOR Previewing a README before you push it. Drafting documentation. Taking notes in Markdown and checking how they will actually look. Composing a comment, an issue, or a pull request description and catching the broken table before anyone else sees it. Two ways to use it: preview Markdown you already have by pasting it in, or start from an empty editor when the text does not exist yet. The preview and the editor are the same window, so there is no step in between. LIVE PREVIEW WHILE YOU TYPE Markdown live preview in the literal sense: the preview is not a separate step. Type a heading and it appears formatted. Add a table and the rows line up. Paste a code block and it stays a code block, monospaced and intact. You never leave the editor to check your Markdown, and you never push a README that renders wrong. GITHUB MARKDOWN AND README PREVIEW Paste your README, issue or release notes and see how the Markdown will render. GitHub Flavored Markdown is supported — tables, fenced code blocks, headings, links and images. Preview your README before you commit it, without leaving the browser. WHAT THE MARKDOWN PREVIEW RENDERS Headings, bold and italic, inline code and fenced code blocks, links and images, nested bullet and numbered lists, blockquotes, horizontal rules, and GitHub-style tables — the Markdown you actually meet day to day in READMEs, docs, issues and notes. MARKDOWN TO HTML — COPY OR DOWNLOAD When the text looks right, one click copies the rendered HTML to your clipboard, ready to paste into a CMS, an email, or anywhere HTML is accepted. Or convert your Markdown to HTML as a file: download a complete standalone .html document with the styling included. YOUR DRAFT IS KEPT Close the popup and come back — your Markdown is still there. The editor saves your draft automatically between sessions, so an interrupted README is not a lost README. EVERYTHING STAYS IN YOUR BROWSER Nothing you write is uploaded. Unlike most online Markdown editors, this one renders locally with plain JavaScript — no server involved, no account, no sign-up, no limits on how much you write, and it keeps working with no connection at all. All text is escaped before it is inserted, and only http(s) and mailto links are allowed, so pasting Markdown from a source you do not fully trust will not run scripts. FULL PAGE OR POPUP Use it in the toolbar popup for quick edits and a fast md preview, or open full-page mode when you are writing something long and want the room. WHO USES IT Developers writing README files and release notes. Technical writers drafting documentation. Product people composing issues and specifications. Anyone who takes notes in Markdown and wants to see the formatted result while writing rather than after — and anyone who just needs a quick Markdown viewer for text somebody else wrote. WRITING AND READING, SAME WINDOW A previewer answers "what does this text look like". An editor answers "what will this look like once I have written it". Most days you need both answers, a few seconds apart. That is the whole tool: open it, type or paste, and see the result.