Free & open source · MIT licensed

Preview medical images, right from Finder.

MIQ is a lightweight macOS Quick Look extension for medical volume images. Press Space on a supported file to instantly get an interactive orthogonal slice view and a metadata panel — no app to open, no waiting.

Universal binary · Apple Silicon & Intel · macOS 14 Sonoma, 15 Sequoia, 26 Tahoe

MIQ Quick Look preview showing a 2×2 orthogonal slice grid and metadata panel
Why MIQ

Built for a quick look —
and nothing else

A convenience tool for quickly inspecting medical image files from the Finder. It prioritizes speed and ease of use over advanced visualization.

⌨️

Just press Space

Native Quick Look integration. Select a file in Finder, hit Space, and the orthogonal slices appear instantly.

🧭

Interactive 4D view

Scrub through slices and volumes, move the crosshair, and adjust window/level — all inside the preview window.

Fast by design

Uncompressed files are memory-mapped and load instantly. Compressed NIfTI is partially decompressed for a quick first frame.

🖼️

Finder thumbnails

Optionally show an image slice as the file icon, so you can recognize volumes at a glance while browsing.

🎛️

Customizable

Tune orientation, intensity scaling, label colors, and the metadata panel content and order in the companion app.

📐

Honest orientation

Shows data as stored on disk by default, so you see the raw orientation. Switch to neurological or radiological view if you prefer.

Formats

The formats you actually use

All formats are supported uncompressed and gzip-compressed.

NIfTI-1 & NIfTI-2
.nii .nii.gz
FreeSurfer
.mgh .mgz .mgh.gz
MRtrix
.mif .mif.gz
✳️
NRRD — experimental
.nrrd · single-file variant with attached header

MIQ relies on the file extension to determine the format — it's important that files have the correct extension.

Get started

Install in under a minute

  1. Install from the command line:
    # tap, trust the cask, and install
    brew tap marcoduering/miq
    brew trust --cask marcoduering/miq/miq
    brew install --cask miq
  2. Open MIQ.app (in /Applications) at least once to register the Quick Look extension.
  3. Press Space on any supported file in Finder.
  4. Optional: customize the preview in the MIQ app.
# later, to update
brew update
brew upgrade --cask miq
  1. Download the latest release (MIQ.app.zip).
  2. Unzip and move MIQ.app to your /Applications folder.
  3. Open MIQ.app at least once to register the Quick Look extension.
  4. Press Space on any supported file in Finder.
  5. Optional: customize the preview in the MIQ app. MIQ checks for updates — open the app occasionally to see update alerts.
Make it yours

Settings for every preference

Adjust render orientation, intensity scaling, label colors, and the metadata panel from the companion app.

MIQ settings — general MIQ settings — appearance MIQ settings — metadata panel
See it in action

A quick look, in real time

Press Space, scrub through slices and volumes, and inspect the metadata — all without leaving Finder.

Video not loading? Watch it on GitHub.

⚠️ Not a medical device. MIQ is not intended for diagnostic use — it is a developer and researcher convenience tool only. Do not use it to make clinical decisions. Provided “as is” under the MIT License, without warranty of any kind.