v0.1.1 · Foldout Folder Preview for Mac

Press Space. See inside any folder.

Foldout turns Quick Look into a folder X-ray: real size, what fills it, the biggest and newest files, and for code projects the git branch and README.

MIT licensed No network access Apple Silicon + Intel
Foldout previewing a code project: size and file-type bar, git branch with two modified files, last commit and the rendered README
real size, subfolders included git branch and last commit README rendered inline zip + Markdown previews macOS 14+
See it in action

74 seconds, start to finish.

How it works

Select. Space. Know.

Finder's Quick Look shows a folder as a big blue icon. Foldout shows you what's actually in it.

Select a folder

In Finder, on the Desktop, or in any app that uses Quick Look. Downloads, projects, photo shoots, client handoffs.

Press Space

Foldout scans everything inside in the background. Numbers fill in live, so you never wait on a spinner.

See what matters

Size and file types at the top. Contents, largest and recent files in tabs. Git and README when it's a project.

Problems it solves

If you've ever searched for one of these…

Finder hides most of what you want to know about a folder until you open it, or open Get Info, or open Terminal.

How do I see a folder's size on Mac without Get Info?

Select it and press Space. Foldout adds up every file in every subfolder and shows the total, the file count and when anything inside last changed.

What's taking up space in this folder?

The type bar shows how much is video, images, code or documents. The Largest tab lists the 100 biggest files anywhere inside, with the subfolder each one lives in.

How do I preview a folder's contents in Quick Look?

macOS doesn't do it on its own. With Foldout, Quick Look shows a sortable table of everything in the folder, with sizes that include subfolders.

Which files in this folder changed most recently?

The Recent tab lists the 100 newest files from all subfolders, not just the top level. Handy for downloads and shared drives.

Can I see a repo's git branch from Finder?

Yes. Press Space on a project folder to see the branch, the last commit and its author, and how many tracked files are modified or deleted.

How do I look inside a zip without unzipping it?

Select the .zip and press Space. Foldout lists its files with their real, uncompressed sizes. Nothing is extracted.

How do I preview Markdown files in Finder?

Foldout renders .md files with headings, lists, code blocks, quotes and tables, offline, in light or dark mode.

Is there a free Quick Look folder preview?

Foldout is free and MIT-licensed. The comparison page lines it up against the paid and free alternatives.

Features

A folder dashboard, one keypress away.

Everything below runs on your Mac, in a sandboxed, read-only extension with no network access.

Real folder size

Every file in every subfolder, counted in the background. Huge folders stop after 15 seconds and show what they found.

File-type breakdown

One bar shows how much space video, images, code, documents, archives and audio take, with counts.

Contents, Largest, Recent

Sortable tables: what's at the top level with full sizes, the 100 biggest files inside, and the 100 newest.

Git at a glance

Branch, last commit, author, date, and counts of modified and deleted files. Read straight from .git, linked worktrees included.

README inside the preview

A project's README opens rendered: headings, lists, code blocks, quotes and tables. Standalone .md files too.

Image grid

Folders that are mostly photos open straight to thumbnails, sorted by name.

Zip contents

Press Space on a .zip to see every file, the uncompressed size and the type breakdown, without extracting.

Light and dark

Native SwiftUI that follows your system appearance. Universal binary for Apple Silicon and Intel.

Private by design

Sandboxed and read-only. No network access, no analytics. It skips other apps' data and cloud drives instead of asking.

Screenshots

What you see when you press Space.

Sample folders, generated for these screenshots.

A code project in dark mode: type bar, git card and the Contents table sorted by size
Code project. Branch, last commit and uncommitted changes above a size-sorted table.
A folder of product photos shown as a thumbnail grid
Photo folder. Mostly images? It opens straight to the grid.
The Largest tab listing the biggest files across all subfolders
Largest files. The 100 biggest files anywhere inside, with their subfolder.
A zip archive previewed without extracting, listing its files and sizes
Zip archive. Files and uncompressed sizes, nothing extracted.
Install

Two minutes, start to finish.

Homebrew builds Foldout on your Mac, so there's no security prompt. Or download the app.

Option 1 · Homebrew (recommended)

No security prompt

Homebrew builds Foldout from source on your own Mac, so macOS never shows the "Not Opened" dialog.

zsh
$ brew install justadityaraj/tap/foldout
$ ln -sf \
    "$(brew --prefix)/opt/foldout/Foldout.app" \
    /Applications/
$ open /Applications/Foldout.app

# later: brew upgrade foldout

Prefer to build it yourself? git clone the repo and run ./scripts/build.sh --install.

Option 2 · Download

Drag into Applications

  1. Download Foldout.dmg, open it and drag Foldout into Applications.
  2. Open Foldout. macOS says "Foldout.app" Not Opened because the app isn't notarized. Click Done.
  3. Go to System Settings → Privacy & Security, scroll to Security and click Open Anyway. Confirm, then click Open. Only needed once.
Open Privacy & Security ↗
Then

Foldout's window shows Quick Look extension is on. Opening the app once is all it needs.

Done

Select any folder in Finder and press Space.

Who built this
Aditya Raj Singh
Aditya Raj Singh
open-source builder

I build small, focused open-source tools for the Mac. Foldout started because I kept opening folders just to find out what was in them. Also by me: Switchboard Browser Picker. More at adityarajsingh.com.

Questions

Foldout, answered.

What is Foldout?
A free, open-source Quick Look extension for macOS. Select a folder in Finder and press Space to see its real size including subfolders, a file-type breakdown, the largest and newest files, and for code projects the git branch, last commit, uncommitted changes and rendered README. It also previews zip archive contents and Markdown files.
Does Foldout change or upload my files?
No. The extension is sandboxed, read-only and has no network access. It never writes to the folders you preview and collects no analytics. It skips Mail, Messages, other apps' data and cloud-drive folders rather than asking you for access.
How does it read git info without running git?
It reads the .git folder directly: HEAD and refs for the branch, the commit object for the last commit, and the index to count modified and deleted tracked files. Packed repos and linked worktrees work too. Untracked files aren't counted.
Why does macOS warn me when I open it?
The downloaded app isn't notarized by Apple, so the first launch shows "Foldout.app" Not Opened. Click Done, then go to System Settings → Privacy & Security and click Open Anyway. To skip the prompt, install with Homebrew: brew install justadityaraj/tap/foldout, which builds the app on your Mac.
Another app's folder preview shows up instead. What do I do?
macOS uses one Quick Look extension per file type. Open System Settings → General → Login Items & Extensions → Quick Look and turn off the other folder preview extensions. Then run qlmanage -r in Terminal.
What do I need to run it?
macOS 14 Sonoma or later, on Apple Silicon or Intel. Building from source needs the Xcode Command Line Tools.

Stop opening folders just to see what's inside.

Free, open source, and two minutes to set up.