DICOM Viewer for Mac — Open .dcm Files in Your Browser (No Install)

Browser-based — no Mac App Store approval

Most desktop DICOM viewers for Mac (Horos, OsiriX, Weasis) require a download, sometimes a license key, and occasionally admin approval from your IT team. The Saga viewer skips all of that — it loads as a web page, parses .dcm files locally in your browser, and renders them with the same OHIF v3 engine used by research hospitals worldwide.

Because the viewer runs client-side, your file never touches Saga servers. Drop the file in, the browser parses the pixel data, applies window/level, and shows you the image. Close the tab and the data is gone from memory.

Works on every current Mac

The viewer is tested on:

• macOS Sonoma / Sequoia — Safari 17+, Chrome 120+, Firefox 120+
• macOS Ventura — Safari 16, Chrome 101+, Firefox 103+
• Apple Silicon (M1/M2/M3/M4) — native WebAssembly performance; large studies render fast
• Intel Macs — also supported, slightly slower WASM decoding on older CPUs

Don't have a supported browser? Install the latest Chrome or Firefox from their official sites — both are free and don't require admin rights on a personal Mac.

What you can do on Mac

• View any .dcm file — drag one file, a folder, or a DICOMDIR set.
• Inspect tags — click the tag browser toolbar for the full tag tree, VR, and values.
• Capture to PNG/JPG — save the current viewport as an image for a report or slide.
• Connect to a DICOMweb server — point at your PACS's WADO-RS endpoint for live browsing.
• Measure + window/level — standard radiology viewing tools built in.

Mac-specific notes

Safari vs Chrome vs Firefox

All three work. Chrome and Firefox tend to handle large multi-frame series (CT/MR volumes) faster because their WASM engines are slightly more optimized for Cornerstone3D's render path. Safari is fine for most single-study review, and stays out of your way on resource-constrained M-series Macs.

DICOMDIR folders

The viewer reads the DICOMDIR index file and walks the folder structure locally. Drag the whole folder in — browser File System Access APIs handle the rest.

"Files never leave your Mac"

This is a structural guarantee, not a privacy policy. The viewer's code is open-source (OHIF v3, MIT); the only outbound network call you'll see in DevTools is to server.dcmjs.org IF you deliberately load the demo dataset. Local files stay local.

Alternatives on Mac (if the browser isn't an option)

Some workflows still prefer installed desktop software. Credible free options for Mac:

• Horos — open-source OsiriX fork, Mac-only. Full diagnostic-style UI.
• Weasis — cross-platform Java-based viewer. No Mac-native polish, but reliable.
• MicroDicom DX (web) — Windows-first but offers a web viewer that also runs on Mac.

All three still require separate workflow (launch app, import file, wait for parse). The browser viewer fits the "I just need to see this file" case in a single drag-drop.

Mac-specific FAQ