Simple Markdown Viewer

About Simple Markdown Viewer

SimpleMarkdownViewer is a small, fast, native Windows app that opens Markdown files and renders them beautifully — and now lets you edit them too. No sign-in, no accounts, no telemetry. Just a clean reading and writing experience for your .md files.

Whether you're browsing README files, reviewing technical docs, or writing notes in Markdown, SimpleMarkdownViewer stays out of your way and lets the content shine.

What you can do
Open any .md file instantly — double-click, use the file picker, drag-and-drop, or pick from the recent files menu.
Edit mode (Ctrl+E) — switch the rendered view into a monospace editor, make changes, and save with Ctrl+S. An unsaved-changes indicator appears in the title bar.
Split view (Ctrl+2) — write on the left, watch the live preview update on the right. Drag the splitter to resize each panel.
Scroll sync in split view — toggle Sync to lock both panels to the same source line. Scroll either side and the other follows instantly.
Caret halo — in split view the preview highlights the block that matches your editor caret with a soft amber glow, so you always know where you are in the rendered output.
Editor word wrap — toggle word wrap in the editor; the setting is remembered across sessions.
Always-on-top (pin) — keep the viewer floating above other windows while you reference your notes.
Viewer font picker — choose the font family used in the rendered preview to match your reading preference.
Editor stats bar — see the current line number and total word count while editing.
Reading progress bar — a thin accent-colored line at the top of the page tracks your scroll position so you always know how far through a document you are.
YAML front matter card — files with --- front matter (Jekyll, Hugo, Astro, Obsidian) show the metadata in a collapsible card above the content instead of rendering it as garbled text.
Copy raw Markdown source — copies the file's raw .md text to the clipboard in one click, without entering edit mode.
Open containing folder — highlights the current file in File Explorer from the overflow menu.
Mermaid diagrams — flowcharts, sequence diagrams, ER diagrams, Gantt charts, pie charts, and more render inline, themed to match your light or dark mode.
Export as PDF — save a print-ready PDF of the rendered document in one click, with no print dialog needed.
Open in external editor — jump straight to your default text editor or IDE from the overflow menu.
Heading navigation (Ctrl+] / Ctrl+[) — jump to the next or previous heading without touching the mouse.
Remembers window size and position — the app reopens exactly where you left it.
Copy with light-mode styling — copied Markdown HTML is always light-themed, so it pastes cleanly into any app regardless of your Windows theme.
Auto-reload on save — keep the viewer open while you edit in your favorite editor. Changes appear automatically, and your scroll position is preserved.
Follow system theme — light and dark themes switch automatically with Windows. Prefer one? Toggle it manually anytime.
Find in page (Ctrl+F) — quickly search the rendered document using the browser's built-in find.
Syntax highlighting — code blocks are highlighted with a clean GitHub-style theme that matches your light/dark preference.
Table of Contents sidebar — a resizable, scroll-synced TOC built from your document's headings, with an active-section indicator.
Remembers your place — reopen a file and you're right back where you left off, per file.
Zoom controls — 75 %–200 % zoom via buttons or Ctrl+scroll, preserved across refreshes.
Export as HTML — save a standalone, self-contained HTML file of the current document.
Print-ready — a proper print stylesheet for sharing docs offline.
Wikilinks (filename) — link between local Markdown files using Obsidian-style filename or display text syntax. Click a link to open the target file; broken links (file not found) appear in red so you can spot them immediately.
Math rendering — inline ($E=mc^2$) and display ($$...$$) LaTeX expressions render beautifully using KaTeX — fast, accurate, no external account needed.
Spell check — the built-in editor underlines misspelled words; right-click for suggestions.
Click-to-open links — external hyperlinks open in your default browser; in-document anchors smooth-scroll within the viewer.
File association — set SimpleMarkdownViewer as the default app for .md files and open them straight from File Explorer.

Why you'll like it
Simple. View or edit, your choice. No plug-ins, no menus to get lost in.
Fast. Native Windows app (WinUI 3) using WebView2 for rendering. Opens instantly, even on large files.
Offline. Your files never leave your machine. No accounts, no cloud sync, no tracking.
Rich Markdown support. Powered by Markdig's advanced pipeline — tables, footnotes, definition lists, task lists, strikethrough, auto-links, math expressions, wikilinks, and more.
Looks right. Clean GitHub-inspired typography with polished light and dark themes.

Full feature list
Reading progress bar — thin accent line at top of page tracks scroll position
YAML front matter card — collapsible metadata card for Jekyll/Hugo/Astro/Obsidian files
Copy raw Markdown source to clipboard (overflow menu)
Open containing folder — highlights file in File Explorer (overflow menu)
Mermaid diagram rendering — flowcharts, sequence, ER, Gantt, pie, and more; light/dark themed
Export as PDF — one-click PDF export via WebView2, no print dialog
Open in external editor — opens current file in the system default editor or IDE
Heading navigation — Ctrl+] / Ctrl+[ to jump between headings
Remembers window size and position across sessions
Drag-and-drop to open
Recent files menu (last 10 files with relative timestamps)
Edit mode — full-screen monospace editor (Ctrl+E), save with Ctrl+S, dirty-state indicator
Split view — editor + live preview side by side (Ctrl+2), draggable splitter
Scroll sync in split view — Sync toggle button; both panels track the same source line
Caret halo — amber glow in the preview highlights the block matching the editor caret; auto-dismisses after 1.5 s of inactivity
Editor word wrap with persisted setting
Always-on-top (pin) toggle
Viewer font family picker
Editor stats bar — current line number and word count
Copy to clipboard with light-mode CSS so paste looks correct in any app
Auto-reload on file change (live preview while editing in another app)
Follow system theme automatically, with manual override
Find in page (Ctrl+F, WebView built-in)
Syntax highlighting for code blocks (highlight.js, light/dark)
Table of Contents sidebar with active heading indicator and drag-to-resize
Per-file scroll-position memory
Zoom in / out via buttons or Ctrl+scroll wheel (75 %–200 %)
Export current document as standalone HTML
Print (Ctrl+P)
Refresh (F5 / Ctrl+R)
Copy file path to clipboard
Wikilinks — filename and text navigation between local Markdown files; broken links highlighted in red
Math rendering — inline $...$ and display $$...$$ LaTeX via KaTeX
Spell check in the editor with right-click suggestions
Smooth scroll for in-document anchor links
External links open in your default browser
File association with .md
Welcome screen with quick open
Remembers last opened file
Built-in Help dialog with feature overview and keyboard shortcuts

Keyboard shortcuts
Ctrl+O — Open file
Ctrl+E — Toggle Edit mode
Ctrl+2 — Toggle Split view
Ctrl+S — Save (while in Edit or Split mode)
Ctrl+F — Find in page (WebView built-in)
Ctrl+] — Jump to next heading
Ctrl+[ — Jump to previous heading
F5 / Ctrl+R — Refresh
Ctrl+P — Print
Ctrl+scroll — Zoom in / out
Ctrl+Z — Undo (in editor)
Ctrl+Y — Redo (in editor)
Tab (in editor) — Insert 4 spaces
Esc — Close window (confirmation prompt)

Supported Markdown features
Headings, paragraphs, emphasis, strong, inline code, fenced code blocks with syntax highlighting, blockquotes, ordered and unordered lists, task lists, tables, horizontal rules, images, hyperlinks, auto-links, wikilinks (filename), footnotes, definition lists, strikethrough, superscript/subscript, highlighted text, keyboard input, abbreviations, math expressions (KaTeX), Mermaid diagrams, and more.