DICOM Sample Catalog

Free Sample DICOM Files

Curated public DICOM studies covering 7 modalities — CT, MR, mammography, X-ray, PET, ultrasound. All CC-BY licensed (commercial reuse OK with attribution), sourced from NCI Imaging Data Commons. No signup. Click Open in viewer on any tile to load the study in our browser-based viewer.

MR · BRAIN MR · 256×256 · T2 US · OBSTETRIC US · multi-frame CT · CHEST CT · 512×512 · 16-bit Curated public studies CT · MR · US · X-Ray · PET · Mammography CC-BY 4.0

What is a DICOM sample file?

A DICOM sample file — also called an example DICOM file or .dcm test file — is a real medical imaging study, such as a CT, MRI, mammogram, X-ray, PET, or ultrasound scan, shared publicly for testing, software development, training, and learning. These example files are de-identified, so they carry no patient data, and open in any DICOM viewer.

Browse the catalog

28 representative studies across 7 modalities. Every tile deep-links into the viewer with the study pre-selected on the worklist — one click and you’re reviewing real DICOM data.

CT Sample Files

Computed-tomography studies are multi-slice volumetric scans reconstructed from X-ray projections. These samples are real axial series — ideal for testing slice scrolling, Hounsfield window/level, and multiplanar reconstruction. Open one in the browser viewer to step through the stack.

IOD
CT Image
Modules
25 · 11 required
SOP Class UID
1.2.840.10008.5.1.4.1.1.2
Full CT Image IOD spec
Healthcare AI integration Take CT imaging AI from algorithm to deployment See how we connect it

MR Sample Files

Magnetic-resonance studies capture rich soft-tissue contrast across multiple sequences (T1, T2, FLAIR). These multi-frame volumetric series are good for testing sequence navigation, window/level, and multi-series handling. View a study in your browser, or inspect its headers with the tag editor.

Ultrasound DICOM Samples

Ultrasound studies are often multi-frame cine loops or single sector images, sometimes with color-flow overlays. These samples are great for testing cine playback, frame stepping, and ultrasound photometric handling. New to the format? See how to view .dcm files.

IOD
Ultrasound Image
Modules
25 · 9 required
SOP Class UID
1.2.840.10008.5.1.4.1.1.6.1
Full Ultrasound Image IOD spec
Medical imaging integration Wire ultrasound into EHR orders & results See how we connect it

X-ray Sample Files

Digital radiography (DX/CR) produces large single-frame projection images — the smallest, fastest .dcm samples to download and a quick way to test rendering, thumbnails, and window/level. New here? Start with what is a DICOM file, or inspect one in the DICOM validator.

IOD
Digital X-Ray Image
Modules
35 · 12 required
SOP Class UID
1.2.840.10008.5.1.4.1.1.1.1
Full Digital X-Ray Image IOD spec
Medical imaging integration Stream X-rays to any browser over DICOMweb See how we connect it

Mammography Test Files

Mammography (MG) studies are high-resolution single-frame breast images, usually in standard views (CC, MLO) with high bit depth. These samples exercise high-dynamic-range rendering and presentation handling. Open one in the viewer to inspect the full-resolution image.

IOD
Digital Mammography X-Ray Image
Modules
37 · 15 required
SOP Class UID
1.2.840.10008.5.1.4.1.1.1.2
Full Digital Mammography X-Ray Image IOD spec
Medical imaging integration Consolidate mammography & priors across sites See how we connect it

PET Sample Studies

PET studies are functional volumetric scans showing metabolic uptake, most often paired with CT as PET/CT. These samples help test multi-series studies, fused display, and SUV handling. Open one in the browser viewer, or see how PET data moves through a DICOM query/retrieve workflow.

IOD
Positron Emission Tomography Image
Modules
27 · 14 required
SOP Class UID
1.2.840.10008.5.1.4.1.1.128
Full Positron Emission Tomography Image IOD spec
Medical imaging integration Turn PET/CT studies into structured reports See how we connect it

Nuclear Medicine Samples

Nuclear-medicine (NM) studies capture gamma-camera images of radiotracer distribution — planar scintigraphy and multi-frame dynamic series. These samples test NM-specific multi-frame handling. Learn how PACS stores and routes nuclear-medicine studies.

IOD
Nuclear Medicine Image
Modules
35 · 15 required
SOP Class UID
1.2.840.10008.5.1.4.1.1.20
Full Nuclear Medicine Image IOD spec
Medical imaging integration Connect nuclear-medicine studies to Epic See how we connect it

How to open a DICOM sample file

  1. Choose a study — pick a sample from the catalog by modality.
  2. Download or open in the viewer — download the .dcm instance or the full .zip, or click Open in viewer to view it in the browser.
  3. Review it — explore the study in the viewer (pan, zoom, window/level, and step through series and frames), or open a downloaded .dcm or .zip in any desktop DICOM viewer.

About this catalog

Saga IT curates CC-BY-licensed studies from NCI Imaging Data Commons and hosts them here for direct download. Each study was downloaded from IDC’s public data buckets and is redistributed under its original Creative Commons Attribution license (CC BY 3.0 or 4.0). The source collection is linked on every tile, and the full data citation is bundled inside each study’s series.zip as a CITATION.txt file.

The 28 studies in this catalog are a hand-curated subset selected to represent clinically interesting examples across 7 modalities. For the full IDC archive — over 85,000 studies — use the browser-based DICOM viewer or query IDC directly via their DICOMweb endpoint.

Sample DICOM Files — FAQ

What is a DICOM file?

A DICOM file (.dcm) is the standard format for medical images. It bundles the image pixels — from a CT, MRI, X-ray, ultrasound, or PET scan — together with a metadata header describing the patient, study, and acquisition settings, so the image stays correctly identified across any imaging system. DICOM stands for Digital Imaging and Communications in Medicine.

Where can I download free DICOM sample files?

You can download free DICOM sample files directly from this catalog — 28 curated studies across 7 modalities, all CC-BY licensed and free for commercial use with attribution, sourced from NCI Imaging Data Commons. Each study offers a single .dcm instance and a full-series .zip.

Can I use these samples commercially?

Yes — every sample in this catalog is CC-BY licensed (Creative Commons Attribution 3.0 or 4.0), which permits commercial use with attribution. We exclude non-commercial (CC BY-NC) collections from the catalog. Cite the original collection per the attribution shown on each tile.

What is the difference between DICOM and DCM?

There is no real difference — DICOM and DCM refer to the same thing. DICOM is the medical-imaging standard; .dcm is the file extension for files saved in that format. Some DICOM files use .dicom or no extension at all.

How do I open a DICOM (.dcm) file?

Open a .dcm file with a DICOM viewer — standard photo apps cannot read it. The fastest option is a browser-based viewer: click Open in viewer on any sample above — no install. Desktop alternatives include MicroDicom, Horos, and Weasis.

Are these DICOM sample files anonymized and safe to use?

Yes — every DICOM sample file in this catalog is de-identified per HIPAA Safe Harbor before entering the archive. The patient identifiers visible in the metadata are randomized study IDs (e.g. 172205^LSS), not real patient data.

How big are these files?

Single-frame studies (X-ray, mammography) are typically 1–15 MB. Multi-frame volumetric studies (CT, MR, PET) range from 30 MB to several hundred MB depending on slice count and resolution. Each tile shows the exact size of both the single-instance .dcm and the full-series .zip before you download. If you open a study in the browser viewer instead, it streams data lazily via WADO-RS — so the viewer loads instantly without fetching the whole study.

What other public DICOM data sources are out there?

Beyond IDC, notable open repositories include TCIA directly (NBIA REST, no DICOMweb), NBIA (TCIA’s data portal), the NIH Chest X-ray dataset, Stanford MURA (musculoskeletal X-ray), and MIMIC-CXR. For the OHIF viewer specifically, you can also point it at the OHIF demo server — we ship that as a secondary data source in our viewer too.