PostDICOM is a free Online DICOM Viewer. You can use it everyday as free DICOM Viewer. Upload, view and share medical DICOM images. We provide 50GB free medical storage, use as an online, free DICOM Viewer. PostDICOM.com is a cloud-based DICOM viewer. It is also a HTML5 zero-footprint DICOM viewer.

The best free software solutions for DICOM images

• PACS-DICOM Viewer. RadiAnt is a PACS-DICOM viewer for medical images designed to provide you with a unique experience. We have refreshed the tutorial showing how to install RadiAnt on Mac computers. This video depicts the installation process on the latest macOS High Sierra systems.
• Download Philips multi-modality DICOM Viewer R3.0 SP13 (file size 77MB) Instructions: Click on the link, then select 'Open' to run the application from this location or 'Save' to place it on your computer's local drive for execution at a later time.

Sometimes it's useful to be able to view and manipulate medical images such as X-rays, CT or MRI scans on your own PC, laptop or tablet. This is particularly important when preparing teaching files or practising for your radiology exams. Finding a good free DICOM viewer can be tricky, especially as there are so many options out there. We have tested may different applications (so you don't have to) and the following are our best picks. We grouped them according to the operating system used because unfortunately there aren't any free viewers that run on both!

A popular software for radiologists working in the UK is currently a programme called 'Horos'. This is a free open source version of the software used by the Royal College of Radiologists for the viva part of the Final FRCR 2B exam, so obviously it makes sense to use it for teaching as well. This programme is only available on Apple computers, hence why so many radiologists own MacBooks.

There is a paid version of Horos called 'OsiriX MD', which is produced by Pixmeo, however it is expensive so not ideal for basic teaching purposes, although has great functionality. Pixemo also produce a free demo version called 'OsiriX Lite', however there are major limitations placed on this including pop-ups asking you to upgrade to the paid version, performance restrictions, image viewing restrictions and inability to edit the meta-data attached to DICOM images - for example you can't easily re-order series within a study, which may be important if you are preparing cases for teaching or examinations. It is for these reasons that we do not list OsiriX Lite in our recommendations.

• The OsiriX UK user group are a group of Radiologists in the UK who are keen on digital radiology education and use OsiriX/Horos for teaching. The aim is to achieve a nationally agreed consensus on how cases are collected, organised and used for teaching and examination and thereby achieve a collective common ground/platform/standard for radiology education across the country. The resources on this site are amazing so we recommend you visit it now!

Software for Apple MacOS

Radiology Cafe's top pick:

Main features

• Intuitive user interface and customisable toolbars
• 64-bit
• Advanced manipulation and measurement tools
• Multi-planar reconstruction (MPR) with thick slab (Mean, MIP, Volume Rendering)
• 3D MIP, 3D Volume rendering, 3D surface rendering
• Image fusion for PET-CT & SPECT-CT
• Reads and displays all DICOM files
• DICOM Editing
• OsiriX migration assistant
• Telephone and E-mail Support Available
  more feature details...

System requirements

• OS: MacOS X 10.8 or higher

Horos should run on any Mac brought within the last 3 years.

Why we like it

We really like Horos as it is a free open source version of the same software as that used by The Royal College of Radiologists for the viva part of the final FRCR (Part B) exam. Becoming familiar with Horos will help radiology trainees when preparing for this exam. Horos is easy to use and there is a huge amount of functionality contained within. It is based upon OsiriX, however it doesn't have the software restrictions that 'Osirix Lite' has meaning that it is a fully functional 64-bit medical image viewer for MacOS X. It was released in 2015 and is updated regularly. We believe Horos is the best free DICOM viewer for Apple MacOS.

Interestingly, Horos is named after the Egyptian god Horus, son of Osiris and Isis. Horos is a based on OsiriX, named after Osiris. The developers obviously appreciate Egyptian and greek mythology!

Visit the Horos website to download the Horos DICOM viewer!

• There is a useful Mac plug-in for Horos that allows you to quickly upload selected studies / images to Radiopaedia, a free educational radiology resource with one of the web's largest collections of radiology cases and reference articles.
• User guide and installation guide:
  https://radiopaedia.org/blog/radiopaedia-plugin-for-horos-osirix

Software for Microsoft Windows

Radiology Cafe's top pick:

Main features

• Simple and intuitive interface with full-screen mode
• Standard manipulation and measurement tools
• Browse several series concurrently in multiple windows with automatic synchronization between series and cross reference lines in series with different image planes
• Display of dynamic sequences/series (CINE)
• Multiplanar Reconstruction (MPR)
• Fusion of series with different modalities (e.g. PET-CT) or different protocols (e.g. MRI T1/T2–DWI)
• Huge range of DICOM file types supported and support for DICOM overlays
• Export DICOM files to JPEG, BMP and WMV.
• Copy and paste directly into Word or PowerPoint documents
• Read DICOM studies from CD/DVD/BluRay disks and local or network folders
• Asynchronous reading (browse images while they are being opened)
• Multi-core and multi-processor support, and advanced memory management system which facilitates concurrent opening of studies with thousands of images
• Universal installer (32 and 64-bit)
• Multilingual interface (>20 languages)
• Multi-touch support for Windows 8
  more feature details...

System requirements

• OS: Windows 10/8/7/Vista/XP (SP2 or SP3)
• Processor: Intel or AMD 1GHz or faster (multicore Intel processor recommended)
• Memory: 512MB of RAM (2GB recommended)
• Hard Disk Space: 5MB of available hard-disk space for installation; additional free space required for image caching
• Screen Resolution: 800x600 (at least 1024x768 recommended)

Why we like it

We really like RadiAnt as it is free, simple, easy to use and very fast. Watch this YouTube demonstration video to see RadiAnt in action. It is downloaded as a single compact application with an installer size of just over 3MB. The application can even run directly from a USB stick! This basic DICOM viever does all the things you would expect and is perfect for revision purposes for radiology trainees.

Visit the RadiAnt website to download the RadiAnt DICOM viewer!

Radiology Cafe's one to watch:

Main features

• Designed mainly for CT and MR DICOM modalities
• 3D reconstruction and volume rendering
• Multi-planar and oblique slicing
• Easily anonymize and de-identify patient scans
• Fast surface extraction and export to STL and PLY formats
• Load DICOM data directly from PACS, CD/DVD, USB or local computer
• Patient search to locate patient data on your PACS
• Loads common non-DICOM file formats: NifTi (.nii), Visualization Toolkit (.vtk), and ANALYZE (.hdr)
• Window/level (brightness and contrast) presets
• Screen capture
• Axis-aligned cropping with context
• Side-by-side comparative assessment
  more feature details...

System requirements

Dicom Reader Mac Os

• OS: Windows 10/8.1
• Processor: Intel i3 or AMD Ryzen 3 (64-bit CPU for data sizes over 100MB)
• Memory: 8+ GB of RAM
• Hard Disk Space: 1GB of available hard-disk space for installation; additional free space required for image caching
• Screen Resolution: 1920x1080 or better

Why we like it

Dicom Reader For Mac

We like Pro Surgical 3D as it is fast and easy to use. Although it is designed for surgeons, it's easy to view patient scans quickly. It works well with studies on CD/DVDs, USB sticks and local DICOM files. The only downside is that this app only works on Windows 10/8.1.

Visit the Pro Surgical 3D website to download the Pro Surgical 3D DICOM viewer!

Radiology Cafe's worth a look:

Main features

• Simple intuitive touch interface
• Basic manipulation, annotation and measurement tools
• Multiplanar (MPR), volume (3D) and X-ray reconstructions
• MIP, simulated x-ray reconstruction and colour palettes
• Customize the layout: 3 views (axial, sagittal, coronal), 4 views (3 + volume) or full-screen display
• DICOM Tags anonymization and DICOM Tags editor
• Import scans directly from local media, PACS or the cloud
• Create and print reports
• Easy to use
• Limitation: A little too basic with minimal functionality
  more feature details...

System requirements

• OS: Windows 10/8.1
• Processor: x64
• Hard Disk Space: 60MB (approx)

Dicom Reader Free Download For Mac

Why we like it

We really like Navegatium as it is free, simple and works very well with touchscreen computers and tablets. It is downloaded as an app from the Windows Store. It is fast and the simple navigation makes it great to use for teaching cases. The only downside is that this app only works on Windows 10/8.1 and feels slightly clunky without a touchscreen... with a touchscreen however, this app rocks!

Visit the Navegatium website to download the Navegatium DICOM viewer!

Online Software

Radiology Cafe's top pick:

Main features

• Free 50GB cloud space to store medical images and clinical documents
• Multi-platform (Windows, MacOS, Linux, IOS, and Android) Support
• Upload, store and view DICOM files
• Upload, store and view non-DICOM clinical documents which are in PDF, BMP, PNG, JPG, MP4 and AVI formats
• Automatic synchronization of compatible series with showing cross-reference lines
• Standard measurement tools
• Ability to anonymize patient data before uploading
• Share patient images with doctors, medical groups, and patients by sending a viewing link and password
• Organize patients into folders and enter custom descriptions to them
• Multiplanar Reconstruction (MPR)
• Maximum Intensity Projection (MIP), Minimum Intensity Projection (MinIP), Average Intensity Projection (AvgIP)
• 3D Reconstruction
• PET-CT, and PET-MR fusion
• Create user groups and manage user Authorizations
• Recycle Bin to prevent accidental deletion
  more feature details...

System requirements

• The following operating systems and internet browsers are supported:
• Windows: Google Chrome, Mozilla Firefox
• Mac OS: Apple Safari, Google Chrome
• Linux: Google Chrome
• iOS: Apple Safari
• Android: Google Chrome

Why we like it

We really like PostDICOM as it is free (up to 50GB online storage), simple, easy to use and fast once the DICOM images are uploaded. As it is cloud based, you can access it on pretty much any device. This DICOM viever does all the things you would expect and is great for sharing studies.

Visit the PostDICOM website to use the PostDICOM viewer!

So there you have it!

Radiology Cafe's 'top pick' and 'one to watch' free DICOM viewers for Microsoft Windows, Apple MacOS and online. Please send us your suggestions for other great free DICOM viewers!