DCM File Viewer
Open .dcm files on Windows, macOS and Linux — with nothing to install.
A .dcm file is a DICOM medical image, and an ordinary photo viewer cannot read one. SoftDicom is a DICOM viewer and portable PACS on an external SSD: plug it in, open the study from the drive, and export it as DICOM, JPEG, PNG or a PDF report.
Quick Summary
A .dcm file is a DICOM medical image, and SoftDicom opens it from an external SSD on Windows, macOS and Linux with nothing installed. It reads CT, MRI, X-ray, ultrasound, mammography, PET/CT, SPECT and cath-lab studies, handles JPEG 2000, JPEG Lossless, RLE and JPEG Baseline compression, and exports a study as DICOM, JPEG, PNG or a PDF report.
What is a .dcm file, and what opens it?
Why an ordinary image viewer will not open it
A .dcm file is not a picture file. Alongside the pixel data it carries the study metadata — patient, series, modality, acquisition parameters, window settings — in the same file. Preview, Photos and Windows Photo Viewer read none of that, which is why a .dcm either fails to open or opens as a single flat frame stripped of everything that made it a study.
A study library, not a folder of files
Studies live in a database on the device rather than as loose DICOMDIR folders, so you browse a library and search it instead of hunting through directories. Import a folder of .dcm files once and the series, not the filenames, are what you navigate.
The same files on Windows, Mac and Linux
The drive is readable on Windows 10/11, macOS 11 or newer and Ubuntu 20.04+ without reformatting, so a study you import on one machine opens on the next. There is no installer on any of them and no administrator password.
Opens with no network at all
Images load from local flash. No VPN, no PACS login, no streaming and no internet connection — which is what makes a .dcm openable on a conference laptop or a machine you have no rights on.
How do I open a DCM file with SoftDicom?
- Plug the SoftDicom SSD into any Windows, macOS or Linux computer.
- Launch the viewer from the drive — there is no installer and no admin prompt.
- Open the study from the device's own study database, or import the .dcm files or the folder that holds them.
How running from a drive works is explained on the portable DICOM viewer page. Platform-specific notes are on the Mac and Linux pages.
Which DCM files does it open?
Full imaging, software and security specifications are on the technical specifications page.
Frequently Asked Questions
What is a .dcm file?
A .dcm file is a medical image stored in the DICOM format, the standard that CT, MRI, X-ray, ultrasound and cath-lab systems write. It holds the image pixel data and the study metadata — patient, series, modality and acquisition details — together in one file, which is why an ordinary photo viewer cannot open it properly.
Is a DCM file the same as a DICOM file?
Yes. .dcm is the usual file extension for a DICOM Part 10 file. Some systems write the same data with no extension at all, or inside a DICOMDIR folder structure, and it is still the same format.
How do I open a DCM file with SoftDicom?
Plug the SoftDicom SSD into any Windows, macOS or Linux computer and launch the viewer from the drive — there is no installer and no administrator prompt. Then either open a study already in the device library, or import the .dcm files, or the folder containing them, and open it from there.
Do I need to install anything to open a DCM file?
No. The viewer runs from the SoftDicom SSD on Windows 10/11, macOS 11 or newer and Ubuntu 20.04+, without installation and without administrator rights. Nothing is copied to the computer and nothing is left behind when the drive is unplugged.
Can I convert a DCM file to JPEG or PDF?
Yes. A study can be exported as DICOM, or as JPEG, PNG, or a PDF report.
Can a scanner send DCM files straight to the device?
Yes, when an administrator enables it. SoftDicom can run a DICOM Storage SCP (C-STORE) with a user-configurable AE Title and port and answers C-ECHO, so a modality on the local network can send studies to the device directly. The listener is disabled by default and stays off until it is turned on.
Your .dcm files, on any computer.
Nothing to install on Windows, Mac or Linux. Choose a capacity and it ships ready to use.