Yes. Skim is completely free and open source under the MIT license, with no Pro tier, no paywall, and no account. Every feature, including folder browsing, math, and diagrams, is available to everyone.

Does Skim upload my files?

No. Skim renders markdown entirely on your device. It collects no data, has no telemetry, and makes no network calls with your content. Files never leave your machine.

Can Skim read local .md files?

Yes. Chrome blocks extensions from local file:// pages by default; Skim walks you through the single 'Allow access to file URLs' switch once, then renders every local markdown file you open.

Does Skim work with AI coding agents?

Yes. Skim is built for reading files an AI agent is actively writing. Leave a plan.md open in a tab and Skim live-reloads it in place, preserving scroll position, every time the agent rewrites the file.

Skim

Free, open-source Chrome extension

Read what your AI wrote. Instantly.

Skim turns raw .md files into beautiful, readable pages right in your browser. Agent plans, READMEs, notes, docs. Everything happens on your device.

Add to ChromeFree · open source · no sign-up Using another browser? See every install option →

Open source, MIT No data collected Works offline Read the source on GitHub →

Skim live-reloading a plan.md as an agent writes it

$Skim rendering KaTeX math and a mermaid diagram$ Skim rendering a document with a contents sidebar

Skim's guided local file-access onboarding

plan.md auto-reloading

An agent is about to write a plan here. Watch the raw markdown on the left become a page on the right, live. When it's done, the left pane is yours to edit.

One click from your browser's store. Free, open source, and MIT-licensed.

Why Skim

Built for the AI era

Live reload

Keep an agent's plan.md open in a tab. Skim re-renders the instant the file changes, scroll position kept.

One-switch local files

Chrome blocks file:// by default. Skim flips the single switch with you, once, then never nags.

Math, diagrams, tables

KaTeX math, mermaid diagrams, GitHub-flavored tables. Hebrew and English bidi done right.

Folder view, free

Browse a folder of markdown and hop between siblings. Other viewers charge for this. Skim never will.

Copy for AI

One click copies the document, or a selection, as clean markdown source, ready to paste back into a chat.

Private by design

No accounts, no telemetry, no network calls with your content. The store privacy line reads: no data collected.

Skim rendering a plan.md file: a contents sidebar on the left, a formatted document with headings, checklists, and code on the right.

The real thing

A document, not a text dump

Every .md file opens with a contents sidebar that tracks where you are as you scroll, syntax-highlighted code, real tables, and light or dark themes. The same page you'd get on GitHub, for files that never leave your machine.

Shown: an agent's plan.md, rendered by the extension.

Honest by policy

How Skim compares

The five-second version. Full, sourced write-up in the 2026 comparison.

	Skim	Markdown Viewer	Markdown Reader
Everything free	Yes, all features	Yes	Pro tier for advanced options
Open source	MIT, current code	MIT	Shipping 3.x is closed
Maintained in 2026	Actively	Last update May 2024	Actively
Guided file access	One-switch onboarding	Manual toggle	Manual toggle
Live reload for agents	Yes, scroll preserved	Auto-reload option	Live preview

No install needed

See it on your own file

Drop any .md file into the free online viewer. Same rendering engine as the extension, entirely in your browser.

New to markdown files? Start with how to open a .md file, or the AI-specific guide: Claude or ChatGPT gave you a .md file?

Your next .md file deserves better than a wall of raw text.

Add to ChromeFree · open source · no sign-up Using another browser? See every install option →