Free browser tool

DICOM TagCompare.

Paste or upload two DICOM tag dumps — from pydicom, dcmdump, dcm4che, DICOM JSON, or a CSV export — and get a clear, side-by-side table of every tag, its name, VR, and value, with matches and differences highlighted. Runs entirely in your browser.

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What is DICOM Tag Compare?

A DICOM instance carries hundreds of attributes as (group,element) tags — patient, study, series, equipment, and image data all mixed into one flat header. When you need to check what changed between two exports (an anonymization pass, a PACS or VNA migration, a scheduled order versus what was actually stored, or two vendors’ exports of the "same" study), scrolling through two raw dumps by eye is slow and error-prone. DICOM Tag Compare is a free, client-side tool for radiology IT and PACS administrators: paste or upload each dump, and it lines every tag up in one table — matching, different, or present in only one side — with plain-language names wherever they’re known. Nothing is uploaded; parsing and comparison happen entirely in your browser tab.

See it in action

Order vs. performed exam — catch a "wo contrast" order that came back "with contrast".
PACS migration drift — line up two exports of the "same" study.

Features

  • Works with pydicom dataset printouts
  • Works with DCMTK dcmdump and dcm4che-style dumps
  • Works with two-line PACS-viewer exports, sequences included
  • Works with a DICOM JSON model (PS3.18 Annex F)
  • Works with a CSV/TSV export with Tag/Description/VR/Value columns
  • Works with plain "Keyword: value" lines
  • Side-by-side diff table — tag, attribute name, VR, value in A, value in B
  • Status badge per row — Match, Different, Only in A, Only in B
  • Sorted numerically by tag
  • Jump straight to differences with one click
  • Search by tag or attribute name
  • Group the table by DICOM module — Patient, General Study, Image Pixel, and more
  • One-click mask of commonly patient-identifying tags before a screenshot
  • Export the current (filtered) comparison as CSV
  • Export the current (filtered) comparison as JSON
  • Single-dataset inspect mode — paste just one dump for a clean, sorted, searchable listing

Under the hood

Client-side only — no uploadNo login, no accountNo server-side storage or loggingCurated DICOM PS3.6 attribute dictionaryWorks with pydicom / DCMTK / dcm4che / DICOM JSON / CSVCSV & JSON export

Questions

What is DICOM Tag Compare?
A free, client-side tool that parses two DICOM tag dumps — from pydicom, DCMTK dcmdump, dcm4che, a DICOM JSON model, or a CSV export — and lines every tag up in one table, flagging matches, differences, and tags present in only one side.
Are my tag dumps uploaded anywhere?
No. Parsing and comparison run entirely in your browser tab. Nothing you paste or upload is sent to a server, and there is no account or server-side log. Refreshing the page clears everything.
Which paste formats does it understand?
pydicom dataset printouts, DCMTK dcmdump and dcm4che-style dumps, a DICOM JSON model (PS3.18 Annex F), a CSV/TSV with Tag/Description/VR/Value columns, and plain "Keyword: value" lines. Unrecognized tags are still shown with their raw hex and value.
Is this a DICOM conformance validator?
No. It is an educational comparison aid for radiology IT and PACS administrators, not a validator against a specific IOD, transfer syntax, or vendor conformance statement.

Try it now

Load one of the built-in synthetic samples to see an anonymization check, a PACS migration diff, and an order-versus-stored mismatch — or paste your own tag dumps straight away.

Open DICOM Tag Compare

Educational comparison aid for radiology IT, not a DICOM conformance validator. Prefer synthetic data when sharing screenshots with others.