# Open a CT or MRI disc on your computer > Got your scan on a CD or DVD from the hospital? Open the DICOM images in your browser on Windows or Mac. No viewer program, no upload, free. The disc from the hospital holds your scan as DICOM files. Put it in a computer with a disc drive, choose the disc here, and the images open in your browser — nothing to install, nothing uploaded. Open your scans here: https://mesdicom.com/open-dicom-cd/ — or at https://mesdicom.com/ You don't need the program that came on the disc. Insert the disc, click **Open a disc or folder…** above, choose the disc drive itself, and MesDICOM finds the images on it. It works in a browser tab on Windows and Mac and is free. ## What is on a hospital disc? Hospitals write scans to discs in the DICOM format, the standard for medical images. Most discs hold the same few things: | On the disc | What it is | Do you need it? | |---|---|---| | A folder of image files, often called DICOM | Your scan: one file per image, often with no file extension | Yes — these are the images | | DICOMDIR | The disc's table of contents | Not on its own. It lists the images; it isn't them | | A viewer program (an .exe, AUTORUN) | Software the hospital ships for Windows | No | | A PDF or a picture | Sometimes the written report or a preview | Not for viewing the images | ## How do I open the disc? 1. Insert the disc. If a viewer program starts by itself, close it. 2. Click **Open a disc or folder…** and choose the disc drive itself. 3. Don't pick DICOMDIR or the viewer program on their own. MesDICOM reads every file and keeps the images. MesDICOM sorts what it finds into studies and series, the way the scanner made them. If the disc holds more than one study, you choose which one to open. You can also drag the disc's icon onto this page. ## What if the browser won't let me choose the disc? Some computers don't offer the disc drive itself in the folder dialog. Then copy the whole disc to a folder on your computer — every folder on it, DICOMDIR included — and choose that folder with **Open a disc or folder…**. It opens exactly the same way. ## Do I need the viewer program on the disc? No. MesDICOM reads the images directly and never runs the program on the disc. That also means a disc made for Windows opens on a Mac. ## My computer has no disc drive. What now? - **Borrow a drive.** An external USB DVD drive costs little and works with any computer. - **Ask for a download.** Many hospitals can send the study as a download link or a ZIP. Open a ZIP with **Open files or a ZIP…** — see [opening a DICOM ZIP](https://mesdicom.com/open-dicom-zip/). - **Copy it once.** Anyone with a disc drive can copy the disc to a USB stick for you. Then open the USB stick like a disc. Phones can't read discs at all. Once the disc is copied to a folder or a ZIP, MesDICOM for iPhone and iPad opens it too. ## What can I do once the images are open? Scroll through the images, change brightness and contrast or pick a window preset, zoom, measure lengths and angles, play a series as a movie, and look at a CT or MR series in three planes or in 3D. **Save to Library** keeps the study in this browser so it opens again next time; otherwise nothing is kept. MesDICOM shows the images; it doesn't interpret them. Your doctor or the radiologist's report explains what they show. ## Questions ### Can I open the disc on a Mac? Yes, in Safari, Chrome, Edge or Firefox. Most Macs have no disc drive any more, so you need an external USB DVD drive — or a copy of the disc on a USB stick, which opens the same way. ### The disc has a PDF report on it. Does MesDICOM open it? No. MesDICOM opens the images. A PDF report opens in your usual PDF reader; MesDICOM tells you if you pick one by mistake. ### How long does a disc take to open? The first image shows as soon as the first series is read. In our tests a 1.5 GB folder of 3,400 images showed its first image in about a quarter of a second and was fully read in under 20 seconds. Optical discs read more slowly than a hard drive, so a disc can take longer. ### Are my scans uploaded when I open the disc? No. Your browser reads the disc and shows the images on your computer. They aren't sent to us or to anyone else. ## Related guides - [DICOMDIR viewer](https://mesdicom.com/dicomdir-viewer/index.html.md): DICOMDIR is a disc's table of contents, not the images. Choose the whole disc or folder and MesDICOM opens the images it lists. Free, in your browser. - [Open a DICOM ZIP](https://mesdicom.com/open-dicom-zip/index.html.md): Got your scan as a ZIP by email, WhatsApp or a hospital download link? Open it in your browser without unzipping. Works on computers and phones. Free. - [DICOM viewer for Windows](https://mesdicom.com/dicom-viewer-windows/index.html.md): Open DICOM files, hospital discs and ZIPs on Windows 10 or 11 in Chrome, Edge or Firefox. Nothing to install, no admin rights, nothing uploaded. Free. Updated October 24, 2026. For viewing and reference only — not intended for diagnosis or treatment decisions.