What's new in Skim
Version 2.3: interactive quizzes embedded in markdown files. Plus 2.2's themes, zen mode, better export, and the clipboard viewer.
See what changed →Everything about reading markdown
Short, honest guides on opening .md files, working with AI agent output, and picking a viewer. Read what's useful, skip the rest.
changelog.mdRelease notes
Release notes
quiz.mdNew in 2.3
New in 2.3
Put a quiz inside a markdown file
Embed an interactive quiz in an HTML comment: invisible on GitHub and in VS Code, rendered by Skim with hints, scores, and review.
Read guide →Skim vs…Comparison
Comparison
The best markdown viewer extensions in 2026
Markdown Viewer, Markdown Reader, and Skim compared honestly: price, open source, maintenance, live reload, and who each one is actually right for.
Read the comparison →intro.mdBasics
Basics
What is markdown?
Plain text with a few formatting marks, explained from scratch: what it is, the core syntax, and where you keep running into it.
Read guide →syntax.mdReference
Reference
Markdown cheat sheet
Every common bit of markdown syntax with a live example beside it. Headings, lists, tables, code, links, task lists, and more.
Open the reference →read.mdChrome
Chrome
A markdown reader for Chrome
What a markdown reader for Chrome does, how to add one in two minutes, and the features worth having once it is set up.
Read guide →firefox.mdFirefox
Firefox
Markdown viewer for Firefox
Render every .md file in Firefox with a free, open-source add-on from Firefox Add-ons, or read one online with nothing installed.
edge.mdEdge
Microsoft Edge
Markdown viewer for Edge
Add Skim from Edge Add-ons and read .md files as formatted pages, local files included. Free and open source.
brave.mdBrave
Brave
Markdown viewer for Brave
A private, open-source markdown viewer for Brave that renders every .md file on-device, no data collected.
opera.mdOpera
Opera
Markdown viewer for Opera
How to add Skim to Opera through the Chrome Web Store and render .md files automatically, free.
vivaldi.mdVivaldi
Vivaldi
Markdown viewer for Vivaldi
Install Skim from the Chrome Web Store in Vivaldi and read every .md file as a clean page. Free, open source.
arc.mdArc
Arc
Markdown viewer for Arc
Arc runs Chromium, so the Chrome Web Store listing installs straight into it. Add Skim and every .md file renders on its own.
safari.mdSafari
Safari
Markdown viewer for Safari
Read .md files in Safari on Mac and iPhone with the free online viewer today, with a native extension on the way.
export.mdGuide
Guide
Convert markdown to PDF
The free, private way to turn a .md file into a clean PDF without uploading it anywhere, plus VS Code and Pandoc options.
Skim.mdOverview
Overview
What is Skim?
The free, open-source markdown viewer for the browser, built for AI-written docs, explained in a couple of minutes.
Read more →file.mdGuide
Guide
How to open a .md file
Every way to open and read a markdown file, and the fastest one on any operating system.
Read guide →chat.mdAI
AI
Claude or ChatGPT gave you a .md file?
Turn an AI chat's raw markdown into a clean, readable page in a few seconds.
Read guide →README.mdGuide
Guide
Open a README.md
Read a project's README the way GitHub renders it, straight from your machine.
Read guide →windows.mdWindows
Windows 11
Open .md files on Windows 11
Default apps, viewers, and the fastest path to a formatted markdown file on Windows.
Read guide →mac.mdmacOS
macOS
Open .md files on Mac
Quick Look, Preview, and browser viewers, and which one actually reads well on macOS.
Read guide →AGENTS.mdReference
Reference
What is an AGENTS.md file?
The convention AI coding agents read to learn your project, explained plainly.
Read reference →CLAUDE.mdReference
Reference
What is a CLAUDE.md file?
How Claude Code uses CLAUDE.md, and what's worth putting in one.
Read reference →Reading a lot of markdown? Skim renders every .md file you open.