DICOM viewer for Mac
Open DICOM files on a Mac without installing anything. Works in Safari and Chrome on any macOS version, including Apple Silicon. Files stay on your Mac.
What it does
macOS has no native DICOM support. Preview and Quick Look will not touch a .dcm file, and the viewer bundled on most hospital discs is a Windows executable that a Mac cannot run at all.
This viewer runs in Safari, Chrome, Firefox or Edge on macOS. There is nothing to install, no Rosetta question and no compatibility problem with Apple Silicon, because the code runs in the browser rather than on the operating system.
Runs in Safari and every other Mac browser
Nothing to install, no security prompt about an unidentified developer.
Works on Intel and Apple Silicon alike
Browser code does not care which chip your Mac has.
Opens the Windows-only disc
The images on a hospital CD are standard DICOM even when the bundled viewer is a .exe.
Everything stays on your Mac
Files are read locally and never uploaded.
How to use it
Copy the files off the disc
Or use the ZIP you downloaded from the hospital portal.
Open this page in your browser
Safari, Chrome, Firefox and Edge all work.
Drag the files in
Finder selections and ZIP archives both work.
View and export
Adjust the image and save a PNG if you need one.
When people use it
The disc only came with a Windows viewer
Very common, and the reason most Mac users go looking for an alternative.
You do not want to install medical software
Desktop DICOM viewers are large and often ask for permissions you would rather not grant.
You are on a managed work Mac
No admin password needed, because nothing is installed.
Supported files
- Uncompressed DICOM (implicit and explicit VR, little and big endian)
- RLE lossless compression
- JPEG baseline and extended, decoded by your browser
- Files with a .dcm extension, and DICOM files with no extension at all
- ZIP archives containing a whole study or several series
Limitations
- JPEG Lossless, JPEG-LS, JPEG 2000 and deflated transfer syntaxes are not decoded — they need heavy codecs we deliberately do not ship. You will get a clear message instead of a blank screen.
- This is a technical tool. It does not read your scan, does not look for findings and does not produce any diagnosis.
- Very large studies of several hundred megabytes may be slow, because all the work happens on your own machine.
Privacy and security
Processed in your browser — nothing is uploaded
Your files never leave your device. Everything runs inside your browser using JavaScript — there is no upload, no server copy and no queue.
Because nothing is uploaded, there is nothing for us to store or delete. Closing the tab removes the files from memory.
We never put file names, patient identifiers or metadata values into analytics or logs. Product events only count how many files were opened.
If you later choose the paid AI explanation, that is a separate, explicit step: you decide which files to attach and nothing is sent until you confirm.
Frequently asked questions
Do I need to install anything on my Mac?
No. This is a web page. It runs in the browser you already use and installs nothing.
Does it work on Apple Silicon Macs?
Yes. Because the code runs inside the browser, the processor architecture makes no difference.
Can macOS Preview open DICOM files?
No. Preview and Quick Look have no DICOM support, which is why a .dcm file shows a blank icon.
What about Horos or OsiriX?
Both are solid native Mac applications and worth installing if you work with medical images regularly. For opening a study once, a browser is faster.