DropSlim

A minimalist drag-and-drop desktop app for macOS to instantly shrink images.

What it does

• Drop or open PNG, JPG, GIF, SVG, WebP, and AVIF — including whole folders (processed recursively)
• Compress with pngquant, mozjpeg (via sharp), SVGO, gifsicle, and sharp for WebP/AVIF
• Review results in a simple list and reveal outputs in Finder
• Tune behavior in Settings — custom save location, .min suffix, subfolder, and more
• Finder Quick Action (macOS) — optimize selected files or folders from Finder

Where the optimized file is saved depends on your settings:

• .min suffix on (default): writes a new file next to the original, e.g. photo.png → photo.min.png. The source file stays untouched.
• .min suffix off: replaces the original file in place with the optimized version.
• minified subfolder: saves into a minified/ folder (with or without .min, depending on the suffix setting).
• Custom save folder: turn off Save optimized files in same folder in Settings — Choose folder appears; click Open to pick a destination.

Download & install (macOS)

No command line or build tools required — use the pre-built app from GitHub.

Requirements

• macOS 11 (Big Sur) or later
• Apple Silicon (M1/M2/M3/…) or Intel Mac (one .dmg for both)

Download

1. Open GitHub Releases (right-hand sidebar on the project page).
2. Pick the latest release.
3. Download DropSlim-<version>-universal.dmg from the Assets section.

Important: Do not use the green Code → Download ZIP button. That archive contains source code only — not a runnable macOS app. Also avoid .zip downloads of the app itself: ZIP archives can strip Unix execute permissions from the binary inside the .app bundle. DropSlim is distributed as a .dmg only.

Install

1. Open the downloaded .dmg.
2. Drag DropSlim into Applications.
3. Eject the disk image.

First launch (unsigned app)

DropSlim is not signed with an Apple Developer ID. macOS will show a security notice the first time you open it. That is expected.

1. Open Applications in Finder.
2. Right-click (or Control-click) DropSlim and choose Open.
3. Confirm with Open in the dialog.

After this one-time step, you can launch DropSlim normally from the Dock, Spotlight, or Applications. Without an Apple Developer ID, macOS cannot fully verify the app — but it is safe to open using the steps above.

Using the app

1. Drop images or a folder onto the window, use the file picker (files and folders), or in Finder right-click an image → Open With → DropSlim.
2. Supported formats: PNG, JPG, JPEG, GIF, SVG, WebP, and AVIF.
3. Optimized files appear in the list; click an entry to reveal it in Finder.
4. Open Settings (footer button, DropSlim → Preferences, or ⌘,). To use a fixed output folder: disable Save optimized files in same folder, then Choose folder → Open.

Credits

Based on the concept of Image Shrinker (CC0-1.0) by Stefan Schulz-Lauterbach. I used his app for all my image optimization tasks outside of a development context. Thank you very much! DropSlim was developed to create a similar app that supports Apple chips.

License

MIT

Copyright (C) 2026-present, Martin Farkas.