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Open DICOM Files in Your Browser, Without Uploading Them
You can view DICOM files in a web browser without installing anything and without uploading them: the AI Web Center DICOM viewer reads the files on your own device, shows the images with window and level, zoom, cine playback and measurements in millimeters, and lists every DICOM tag. Nothing is sent to a server, and closing the file deletes it from the page.
Medical images come as DICOM files: on a CD from the hospital, in a download from a patient portal, or exported from a PACS. Most computers can’t open them, and many online viewers want you to upload them first. For a scan of your own body, that’s a lot to ask.
So I built a DICOM viewer that never sees your files.
How it works
Click Open files or Open a folder, or drop files on the image. The page reads them in your browser tab, on your device. Nothing goes to a server, and nothing is stored. Click Close and delete, open something else, or leave the page, and the files are gone from it.
A folder or a handful of files open as one series, sorted from head to feet. Files that aren’t DICOM are skipped with a note.
What you can do with an image
- Window and level. Drag left and right for contrast, up and down for brightness, or pick a preset: lung, soft tissue, mediastinum, bone, brain.
- Scroll and play. The mouse wheel or arrow keys move through the slices. Clips play at the frame rate stored in the file.
- Zoom, pan, rotate, flip and invert.
- Measure. Distances in millimeters, from the file’s own pixel spacing.
- Read the value under the pointer, in Hounsfield units on a CT.
- Read every tag, grouped (patient, study, acquisition, image), searchable, with sequences folded and private vendor tags marked.
Seven samples to try
No scans of your own? Pick a sample: a chest CT, a breathing chest CT, a beating heart MRI, a brain MRI, a liver ultrasound clip and two chest X-rays. They’re public research images under Creative Commons licenses, credited beside each one, and most can be downloaded as a DICOM file to try in other viewers.
What it opens
Uncompressed files, deflated files, RLE and baseline JPEG, in gray or color, single images or multi-frame clips. Files compressed as JPEG lossless or JPEG-LS still show all their tags, along with the free command that decompresses them.
What it isn’t
A technology demonstration, not a medical device. It’s for looking and learning, not for diagnosis. For what your scan shows, ask for the radiologist’s report.
How it was built
The samples were prepared with the open-source OFFIS DICOM Toolkit (DCMTK). Your own files are read by a small DICOM reader that runs in the page, tested against over a thousand broken and hostile files. The case study has the architecture and the decisions behind it.
Building a patient portal, a referrer portal or a PACS integration? Tell me what you need.