Editing

Peekdown includes a full markdown editor with live preview, syntax highlighting, and formatting shortcuts.

Edit Mode

Press ⌘⇧E to toggle edit mode, or click the edit button in the toolbar. The window expands to show a split view with your editor on one side and a live preview on the other.

  • Editor position — Choose left or right in Settings > Editor
  • Hide preview — Press ⌘⇧P to hide the preview pane while editing
  • Divider — Drag the split view divider to adjust the editor/preview ratio

Changes are reflected in the preview as you type.

Saving

  • ⌘S — Save the current file
  • Dirty indicator — An unsaved file shows a dot in the title bar
  • New files — Press ⌘N to create a new untitled file in edit mode. It opens as a tab of the window you're in; an empty window is reused in place

Formatting Shortcuts

Shortcut Action
⌘B Bold
⌘I Italic
⌘E Inline code
⌘K Link
⌘⌥⇧1 Heading 1
⌘⌥⇧2 Heading 2
⌘⌥⇧3 Heading 3
⌘⇧O Ordered list
⌘⇧U Unordered list
⌘⇧T Task list
⌘⇧. Blockquote
⌘⌥B Formatting toolbar

Scroll Sync

Press ⌘⇧Y to toggle bidirectional scroll sync between the editor and preview. When enabled, scrolling one pane automatically scrolls the other to the matching position.

Math and Diagrams

Peekdown renders LaTeX math and Mermaid diagrams in the preview and in Quick Look. Both are on by default and work completely offline.

Write math with KaTeX:

  • $$ … $$ or \[ … \] for a centered display equation
  • \( … \) for inline math
  • A fenced code block tagged math for a display equation
  • GitHub's $`…`$ inline form

Single-dollar math ($ … $) is off by default, since it can mistake dollar amounts for equations. Turn it on under Settings > Behavior if you want it.

Draw diagrams by putting Mermaid syntax in a fenced code block tagged mermaid — flowcharts, sequence diagrams, class diagrams, and more. A diagram that can't be parsed falls back to showing its source.

Turn math and diagrams on or off under Settings > Behavior. In Quick Look, both always render.

Syntax Highlighting

Toggle syntax highlighting with ⌘⇧S. Peekdown includes eight editor themes:

  • GitHub Light
  • GitHub Dark
  • Dracula
  • Monokai
  • Solarized Light
  • Solarized Dark
  • One Dark
  • Nord

Change the theme in Settings > Editor.

Editor Font

Choose from popular monospace fonts like SF Mono, JetBrains Mono, Fira Code, Menlo, and Monaco. Adjust the font size from 9pt to 32pt in Settings > Editor.

Spell Checking

Spell checking is available but disabled by default. Enable it in Settings > Editor.