Online DICOM viewer
Open a .dcm file, or a whole series, straight in your browser. Nothing is uploaded: the file is read and drawn on your device.
Not for diagnosis. This is a convenience viewer for looking at a file. Clinical reading belongs in a certified viewer. See the medical disclaimer.
Drop .dcm files here, or
Files stay on this device. Several files are stacked by instance number. Folders: drag the files inside.
Drag on the image to change window/level (left–right = width, up–down = centre). Scroll the wheel or use ↑/↓ to move through images.
How to check that nothing leaves your computer
The page loads its code once, then works offline in your tab. To confirm it: open your browser's developer tools, go to the Network tab, load a file, and watch. No request carries the file. The site's security policy also restricts the page to connecting only to its own address, so the browser would block an upload to anywhere else.
What it opens
| Supported | Not supported yet |
|---|---|
| Uncompressed pixel data (little endian, implicit or explicit VR, and big endian); RLE Lossless; baseline JPEG (8-bit); JPEG 2000 and JPEG-LS (lossless and lossy/near-lossless). 8-bit and 16-bit greyscale (including signed CT with rescale slope and intercept), MONOCHROME1 and MONOCHROME2, RGB and YBR colour. Multi-frame files and several files at once. | Lossless JPEG, High-Throughput JPEG 2000, JPEG 2000 Part 2 and deflated files (the tags still show, with an “unsupported transfer syntax” note). Palette colour, 32-bit and floating-point pixels. DICOMDIR and zip archives (drop the files inside). Overlays, presentation states, measurements, MPR and 3D. |
A file that uses an unsupported format is not rejected: its tags are still listed so you can see what it is, and the message names the transfer syntax so you know what to ask for. JPEG 2000 and JPEG-LS are decoded by two small WebAssembly modules that are part of this site (OpenJPEG and CharLS); they are fetched from dicompeek.com the first time such a file is opened, and nothing is sent anywhere.
Controls
- Window/level: drag on the image, or type a centre and width. For CT these are in Hounsfield units after the file's rescale slope and intercept are applied. If the file has no window, the full range of the image is used.
- Series: files with the same Series Instance UID are sorted by Instance Number. Use the slider, the mouse wheel or the arrow keys.
- Zoom: the + and − buttons; Fit returns to the screen size. Pixel spacing is used to show non-square pixels at the right proportion.
- Tags: every element in the file, with its name where the standard dictionary has one. Filter by name, tag number or value. Tags can contain patient details, so they only appear on your screen.
Need pictures rather than a viewer? Use DICOM to JPG.