How to open DICOM files in your browser

What is a DICOM file?

DICOM stands for Digital Imaging and Communications in Medicine. A DICOM file can combine image pixel data with structured attributes describing the modality, study, series, image dimensions, display settings, and other context. Files often use the .dcm extension, but the internal file structure matters more than the filename.

Open a file with MedImages

1. Create an account or sign in to your existing account.
2. Open the viewer workspace.
3. Select Upload, choose a DICOM file, or drag files into the viewport.
4. Wait for validation and upload to complete. The file will appear in the image list.
5. Select the image, then use window/level, zoom, pan, rotate, flip, or invert controls.
6. Open the inspector to review the metadata fields MedImages was able to read.

Uploads are sent to MedImages and stored for your account; this is not a local-only viewer. Review the privacy and file-handling explanation before uploading sensitive files.

Why a DICOM file may fail to open

• It is too large. MedImages currently limits each upload to 4 MB.
• It is not DICOM Part 10. The server requires the standard DICM signature in the file preamble.
• The extension is misleading. Renaming another file to .dcm does not convert it to DICOM.
• The encoding is unsupported. The file may use pixel data, a transfer syntax, or a multiframe structure that the current browser renderer cannot decode.
• The upload is incomplete. A damaged, truncated, or partially exported file may pass through another system but still fail to parse or render.
• Your account has reached its image limit. Remove an existing upload or follow the plan options shown in the workspace.

After the image opens

Use windowing to change the visible intensity range, zoom and pan to examine the image, and the inspector to view selected DICOM tags. If you need a copy of the current view for a presentation or other non-diagnostic workflow, read the DICOM export guide first.