A free, open-source WYSIWYG Markdown editor for macOS and Windows.
Type Markdown and see it formatted instantly. No account, no cloud, no tracking — just your .md files.
Download · Features · Shortcuts · Build from source · 한국어
Most Markdown editors split the screen into "source" and "preview". Nib doesn't: you write in a single, clean page and each element is rendered as soon as its syntax is complete — **bold** turns bold the moment you type the closing **, # becomes a heading the moment you type the space. Markers only reappear while your cursor is inside that element, so you can always edit the raw Markdown without switching modes.
- Live preview, one pane — a distraction-free, seamless writing experience.
- Your files stay plain Markdown — Nib never rewrites what you didn't touch. Opening and saving a file leaves it byte-for-byte identical, including LF/CRLF line endings.
- Local and private — works fully offline, needs no account, and sends no telemetry.
- Built for every language — careful handling of IME input (Korean, Japanese, Chinese) so composing text never jumps or disappears.
- Free and open source — MIT licensed.
| Formatting | Headings, bold, italic, inline code, links, underline, ==highlight==, superscript x^2^, subscript H~2~O |
| Lists | Bullet, numbered and nested lists, task lists with clickable checkboxes, smart Tab / Shift+Tab indentation with automatic renumbering |
| Tables | Edit cells directly, add/move/delete rows and columns, column alignment, resize — or just type |a|b| and press Enter |
| Images | Inline rendering, drag & drop to insert, drag the corner to resize (), relative paths resolved from the document's folder |
| Code blocks | Syntax highlighting for 100+ languages, language picker with icons, auto-closing fences |
| Math | KaTeX inline $...$ and block $$...$$ formulas with live preview and error messages, chemistry via \ce{} (mhchem) |
| Diagrams | Mermaid flowcharts, sequence, state, class, ER, Gantt and pie charts, rendered in place |
| Footnotes | [^1] references shown as superscripts with hover previews; missing definitions are flagged |
| Windows & files | One window per document, open/save/save as, unsaved-change indicator, atomic saves |
| Fonts | Choose body and code fonts (Open Sans, Pretendard, Cascadia Code or system fonts) — bundled, so they work offline |
| Theme | Light and dark, following your system setting |
| Help | Press F1 for a built-in guide to every shortcut and input rule |
Get the latest version from the Releases page.
| Platform | File |
|---|---|
| macOS — Apple Silicon (M1/M2/M3/M4) | Nib-<version>-arm64.dmg |
| macOS — Intel | Nib-<version>.dmg |
| Windows 10 / 11 (64-bit) | Nib-Setup-<version>.exe |
- macOS: open the
.dmgand drag Nib into Applications. The app is signed and notarized by Apple, so it opens without security warnings. - Windows: run
Nib-Setup-<version>.exe. The installer is not code-signed yet, so Windows SmartScreen may show a warning — click More info → Run anyway.
Nib registers itself for .md and .markdown files when installed. To make it the default app for double-clicking:
- macOS: select any
.mdfile in Finder → Get Info (⌘I) → Open with → choose Nib → Change All… - Windows: right-click a
.mdfile → Open with → Choose another app → select Nib → check Always use this app
Linux is not officially supported yet.
Your documents are never stored inside the app, so removing Nib's data does not affect your files.
-
Windows: uninstall Nib from Settings → Apps. App data (
%APPDATA%\Nib) is removed automatically. -
macOS: move Nib to the Trash, then remove its settings and cache:
rm -rf ~/Library/Application\ Support/Nib ~/Library/Preferences/io.github.colinder.nib.plist
Mod is ⌘ on macOS and Ctrl on Windows. Press F1 in the app for the full list.
| Action | Shortcut |
|---|---|
| New / Open / Save / Save as | Mod+N / Mod+O / Mod+S / Mod+Shift+S |
| Bold / Italic / Underline | Mod+B / Mod+I / Mod+U |
| Strikethrough / Highlight / Inline code | Mod+Shift+X / Mod+Shift+H / Mod+Shift+` |
| Insert link | Mod+K |
| Heading 1–6 / Paragraph | Mod+1 … Mod+6 / Mod+0 |
| Quote / Bullet list / Numbered list | Mod+Alt+Q / Mod+Alt+U / Mod+Alt+O |
| Code block / Math block / Table | Mod+Alt+C / Mod+Alt+B / Mod+Alt+T |
| Indent / Outdent list item | Tab / Shift+Tab |
| Line break within a paragraph | Shift+Enter |
| Open link | Mod+Click |
| Settings / Help | Mod+, / F1 |
Type plain Markdown — Nib formats it as you go.
| Type | Result |
|---|---|
# … ###### |
Heading 1–6 |
- * + / 1. |
Bullet / numbered list |
- [ ] |
Task list item |
> |
Blockquote |
--- |
Horizontal rule |
``` + language + Enter |
Code block |
$$ + Enter |
Math block |
|Name|Value| + Enter |
Table |
[^1] and [^1]: note |
Footnote |
A sample document with math, diagrams and footnotes lives in docs/samples/math-and-diagrams.md.
Requirements: Node.js 24 and npm 11.
git clone https://github.com/colinder/Nib.git
cd Nib
npm install
npm run dev # run in development mode
npm test # run tests
npm run typecheck # type-checkBuild installers (output in dist/):
npm run dist:mac # .dmg for Apple Silicon and Intel
npm run dist:win # NSIS .exe for Windows x64macOS builds are signed with the Developer ID certificate in your keychain. To notarize, store credentials once with xcrun notarytool store-credentials "nib-notary", then run APPLE_KEYCHAIN_PROFILE=nib-notary npm run dist:mac.
| Area | Choice |
|---|---|
| Shell | Electron |
| UI | React + TypeScript |
| Editor engine | CodeMirror 6 (live preview via decorations) |
| Math / diagrams | KaTeX, Mermaid |
| Build | electron-vite, electron-builder |
| Tests | Node.js built-in test runner (node --test) |
Design documents (in Korean): Product spec · Technical design · Roadmap
Nib is shaped by its users — ideas are very welcome!
- Request a feature: open a feature request. Describe the problem you're trying to solve and how you'd like Nib to behave.
- Report a bug: open a bug report with your OS, Nib version and the Markdown that reproduces it.
- Ask a question or share a rough idea: start a thread in Discussions.
- Vote on ideas: add a 👍 reaction to existing requests — it helps decide what comes next.
Please search existing issues first to avoid duplicates.
MIT © colinder
Code block language icons are from vscode-icons (MIT). Bundled fonts — Open Sans, Pretendard and Cascadia Code — are licensed under the SIL Open Font License.
Nib은 macOS와 Windows용 무료 오픈소스 WYSIWYG 마크다운 에디터입니다. 마크다운을 입력하는 즉시 서식이 적용되고, 편집 중인 요소에만 원문 기호가 드러나 화면 하나로 글쓰기에 집중할 수 있습니다.
- 실시간 미리보기: 미리보기 창을 따로 띄우지 않고 한 화면에서 바로 렌더링
- 원문 그대로 저장: 손대지 않은 부분은 바뀌지 않고, 줄바꿈(LF/CRLF)도 유지
- 한글 입력 최적화: 한글 조합 중 글자가 튀거나 사라지지 않도록 다듬음
- 표·이미지·코드 블록·KaTeX 수식·Mermaid 다이어그램·각주 지원
- 오프라인·무계정·무추적, MIT 라이선스
다운로드: Releases 페이지에서 macOS(.dmg, Apple Silicon/Intel)와 Windows(.exe) 설치 파일을 받을 수 있습니다. macOS 앱은 Apple 공증을 받아 경고 없이 열립니다. Windows에서 SmartScreen 경고가 뜨면 추가 정보 → 실행을 누르세요.
앱 안에서 F1을 누르면 모든 단축키와 입력 규칙을 한국어로 볼 수 있습니다.
기능 요청·버그 제보: 기능 요청 / 버그 제보 양식으로 남겨 주세요. 한국어로 작성해도 됩니다. 가벼운 질문이나 아이디어는 Discussions에 남겨 주세요.