Filo Markdown

You write Markdown every day. Your reader should be as good as your editor.

Filo is a dedicated Markdown reader and Mermaid diagram viewer for Mac — not an editor, not a browser tab, not an IDE extension. Open any .md file and it renders instantly, entirely offline, with no accounts, no telemetry, and no cloud sync. Write wherever you like. Read in Filo.

Mermaid Diagrams

Mermaid diagrams render inline — flowcharts, sequence diagrams, entity-relationship (ER) diagrams, Gantt charts, state machines, pie charts, and more. Tap any diagram to expand it to a full-screen zoom view. Full-text search works inside Mermaid diagram text, so you can find nodes and labels across your entire document.

Rendering

Full GitHub-Flavored Markdown: tables, task lists, strikethrough, and all standard GFM features. Renders inline HTML embedded in Markdown documents. Code blocks are syntax-highlighted in 40+ languages, with colors that adapt to light and dark modes.

Reading Comfort

Adjust color temperature from 2700K (warm amber) to 6500K (cool daylight) for comfortable reading at any hour. Light, dark, and system appearance modes. Zoom from 0.5x to 2.0x in fine increments. Filo is built for Mac desktop reading — extended sessions with READMEs, documentation, architecture notes, and long-form writing.

Navigation

A floating Table of Contents with nesting indicators lets you scan and jump through long documents. Full-text search finds results across document text and inside Mermaid diagrams. Back/forward navigation tracks your position across documents. A recent files list on the welcome screen remembers what you were reading.

Keyboard-First

Over 20 keyboard shortcuts cover everything: open, search, zoom, appearance, navigation, and print. Trackpad swipe gestures work too. Every action is reachable without touching the mouse.

Workflow

Filo watches your files. Edit in Vim, VS Code, Obsidian, or any text editor — Filo reloads automatically when the file changes, including vim-style atomic saves. Print or export to PDF with the native macOS print dialog. Drag and drop files onto the window or Dock icon.

Privacy

Filo makes zero network calls. No analytics, no tracking, no data collection, no cloud sync. Your files stay on your Mac. Period.

Requires macOS 14.0 (Sonoma) or later.