DICOM (.dcm) Viewer & Anonymizer Tool

About this tool

Analyze medical imaging DICOM files directly in your browser and instantly preview anonymization actions by listing any remaining sensitive metadata such as patient identifiers, GPS-equivalent coordinates, acquisition dates/times, and equipment serial numbers. Draw rectangular masks on the preview to black out specific regions in the pixels, combining metadata scrubbing with pixel masking before export. Use it not only to compare before/after anonymization but also to inspect and review metadata in detail. All processing happens entirely in your browser (no data is sent).

  • Parses DICOM Explicit VR / Implicit VR Little Endian (common CR/CT/MR/US) and Explicit VR Big Endian files, loading the metadata without touching the pixel data.
  • Applies the research preset (full anonymization) by default, with the option to switch to the internal-use preset or fine-tune actions per tag.
  • Add or remove rectangular pixel masks in the preview to black out regions during anonymization.
  • Download the anonymized DICOM locally and keep evidence for each study.

Load a file

Analyze one DICOM file (.dcm / .dicom) at a time. Please extract ZIP archives beforehand.

Drag & drop a DICOM file here You can also click to choose a file. If multiple files are selected, only the first one is analyzed.

Only the metadata portion is read and edited; pixel data is left untouched.

Analysis results

Select a DICOM file to start the analysis.

How to use

  1. Drag & drop a DICOM file (or click to select one). Wait for the browser to finish processing.
  2. Sensitive tags such as patient data, dates, and coordinates are highlighted by category. Adjust the action for each row (keep / blank / fill with zeros / reissue UID) as needed.
  3. Choose the anonymization preset that fits your workflow to apply recommended actions at once. Fine-tune the dropdowns manually if you need adjustments.
  4. Review the planned changes with “Update anonymization preview,” then save the processed DICOM via “Download anonymized file” if everything looks correct.

Notes

  • Supported transfer syntaxes: Explicit VR Little Endian / Implicit VR Little Endian / Explicit VR Big Endian. Compressed Pixel Data (JPEG, etc.) is preserved; only metadata is rewritten.
  • Nested tags inside sequences (SQ) are not parsed. Review objects like RequestAttributesSequence separately if they may contain personal information.
  • UID re-issuance generates decimal strings following the DICOM UID specification (not RFC 4122). Test downstream system compatibility in advance.
  • The anonymized DICOM is produced entirely in browser memory and never sent to any server or cloud.

This tool assists with anonymization checks for research or external sharing; the ultimate responsibility for data handling rests with the user.