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How to view your CT / MRI / ultrasound scan CD in your browser - open it on your phone or PC, no upload

22 Jul 2026

🌐 อ่านหน้านี้เป็นภาษาไทย →

Open a huge, multi-GB MRI, CT scan or ultrasound zip in this free online DICOM viewer - right in the Chrome browser on your tablet, phone or PC. Simple usage: make a zip from the CD, then upload it to your own Google Drive or a similar service just to get it onto your tablet/phone (or use a USB drive instead - or skip this if you're opening it on the same PC). Then on your tablet, phone or PC, download the zip and open Chrome at clearevo.com/dicom - press the blinking top-left button to open that zip.

ClearEvo.com DICOM Viewer is free - no install, no sign-up, and it never uploads your images: they're read straight off your device (verify). No scan of your own yet? I share my own anonymized CT and MRI as demo downloads so you can try it with real data.

Not a medical device - for personal viewing of your own scans, not for diagnosis: that belongs to your radiologist and their certified tools. Provided as is, with no warranty.

Try it with a demo scan (about a minute):

1. Open the ClearEvo DICOM Viewer in a new tab →
2. Press ▶ Try a demo scan (150 MB) - my ear CT with a real SCDS hole, the exact thin-slice series my radiology report points to. (The full 1.2 GB CT and 870 MB MRI CDs are right below it if you want to try the full experience.)
3. Press the blinking Open file button (top-left) and pick the downloaded zip - it opens right up. The zip file is read directly.
4. Scroll with the mouse wheel, or swipe on a phone, to move through the slices.

Open your own scan

1. Get the scan as a zip. Hospitals often give a zip download link - if so, use that and skip to step 2. If you have a CD, make the zip on a Windows PC with a CD drive (or a cheap USB CD drive plugged into any PC):
   • Right-click an empty spot on the Desktop, choose New → Folder, and type a name, e.g. myscan.
   • Put the CD in and open it: double-click This PC, then double-click the CD/DVD drive.
   • Press Ctrl+A (selects all the files), then Ctrl+C (copies them).
   • Double-click your new myscan folder on the Desktop and press Ctrl+V (pastes) - wait until copying finishes.
   • Go back to the Desktop and right-click the myscan folder: pick Compress to ZIP file (Windows 11) or Send to → Compressed (zipped) folder (Windows 10). A myscan.zip file appears next to the folder - that’s the file you’ll open in the viewer.

   An unzipped folder or loose .dcm files work too. (.tar.gz, .7z and .rar aren’t supported - unzip those to a folder and zip that instead.)

2. Open https://www.clearevo.com/dicom/ in the Chrome browser and press the blinking Open file button (top-left), then pick your myscan.zip. On a PC you can also just drag the zip onto the page. On a phone: download the zip first (from your Google Drive or your hospital’s link), then pick it from your Downloads.
3. Pick a series from the thumbnail list on the left (or top if you’re using a phone).
4. The viewer starts in Simple mode: just the essentials, in plain words - Browse (swipe/scroll slices), Brightness, Zoom, 📏 Measure (distance in mm, with Undo pt to remove points one by one), Play for clips, Save image. Picking a tool plays a short animated hint of its gesture right on the image.
5. On a phone it’s a photo app: swipe through slices, pinch to zoom, drag to pan when zoomed, double-tap to zoom.
6. Save image snapshots the current view as a PNG (a small toast confirms the saved file name - look in your Downloads folder).
7. Ultrasound and other moving clips play like video - press Play to run them, or drag the slider to move frame by frame.

The interface is available in English and ไทย (auto-selected from your browser; switch with the language box).

What can it open?

The DICOM format - which is what most medical CDs and USBs are:

• MRI and CT scans - flip through the image slices the same way the radiologist does, with one-tap display presets (soft tissue, brain, lung, bone).
• Ultrasound - still images and moving clips (they play like video, at the clip’s own frame rate). Pregnancy ultrasound CDs work too.
• X-ray / mammogram CDs use the same DICOM format and should open as well - if yours doesn’t, tell me in the comments.

(For clinicians: technical details are in For clinicians below.)

What the demo scans show

The demos show a left superior semicircular canal dehiscence (SCDS) in my inner ear - which is why I built this tool: I wanted to see my own problem directly in Chrome on my phone, without having to find a PC to open the CD. So you can match what you see against a real reading, summarized from the professional radiology reports of these scans (identifying details removed):

• CT temporal bone - “A focal bony dehiscence at the superoposterior aspect of the left superior semicircular canal.” The right inner ear is unremarkable. Open the thin-slice IAC Lt cor obl 0.6 mm series (the reformats along the canal - the demo-button zip contains exactly this series) and pick the Bone window preset.
• MRI brain / base of skull - reviewed for the same: “suspected focal thinning of the bony coverage at the posterior aspect of the left superior semicircular canal; dehiscence cannot be excluded”, with incidental sinus changes. Clinical picture: chronic dizziness.

Download the full CDs (GPL)

I share both anonymized scans for education and testing under the GNU GPL v2 (same license as the site’s tools) - each is the complete CD as a zip, with a LICENSE.txt inside. These are the same files the viewer’s demo buttons download - after downloading, press Open file in the viewer and pick the zip.

• Download the full CT temporal-bone CD (~1.2 GB zip, GPL)
• Download the full MRI brain / base-of-skull CD (~870 MB zip, GPL)

For clinicians

• Switch the toolbar to Advanced mode (dropdown at the right) for the standard vocabulary and full toolset: W/L with CT presets (soft tissue, brain, lung, bone), Pan, Angle, Rotate/Flip (anatomical edge markers are hidden while rotated or mirrored rather than shown wrong), Invert, Tags (every DICOM element), named-PNG export. The choice is remembered on that browser.
• Transfer syntaxes decoded: Implicit/Explicit VR Little Endian, RLE, JPEG Lossless (processes 14/SV1 and 14), JPEG Baseline (8-bit, ultrasound), and JPEG 2000 (lossless and lossy). Multi-frame instances play as cine at the file’s FrameTime.
• Privacy is verifiable, not just claimed: the images are decoded entirely in the browser and never uploaded - how to verify yourself. Free software, GPL v2, source on GitHub.
• There’s a printable one-page hand-out (EN/ไทย, with QR code) you can keep at the counter and give patients together with their CD.

Honest limits

• Decodes uncompressed DICOM, RLE, JPEG Lossless (most CT/MRI CDs), standard JPEG (ultrasound) and JPEG 2000. Not yet: JPEG-LS, big-endian, and video-inside-DICOM (MPEG) - if your CD won’t open, tell me in the comments.
• Opens .zip, an unzipped folder, or loose .dcm files.
• Google Drive folder integration is planned; for now, download the zip first.
• No MPR / 3D reconstructions - this is a viewer for looking at your scan, not a radiology workstation.

Everything is client-side (Google Analytics for visit stats only - verify).

This tool is free software and open source: ykasidit/clearevo_online_tools - issues and pull requests welcome. The demo CT/MRI scans are my own, anonymized, and released under GPL v2.

Full disclosure: this post - and any code or tool it describes - was co-authored with Claude (Anthropic’s AI, via Claude Code). I directed, guided and reviewed. I don’t want to pretend otherwise.

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