DICOM Dictionary

Look up a tag or a transfer syntax, without opening the standard.

Everything on this page runs in your browser. The dictionary is part of the page, so nothing you type here is uploaded and the page makes no request of any kind carrying it.

Find a tag

Search by number or by name. A tag is accepted however you have it written - (0010,0010), 0010,0010, 00100010, or the [0x0010][0x0010] the DICOM Inspector prints.

Tag number or name

Transfer syntaxes

What the UID in (0002,0010) means, and whether anything happened to the pixels. Compressed and lossy are different questions - RLE and JPEG Lossless are both compressed and neither has changed a value.

Transfer syntax UID or name

Value formats that catch people out

PN - a person name has five components

family^given^middle^prefix^suffix

Separated by ^, and trailing empty ones are usually omitted - so SMITH^JOHN is a complete PN, not a truncated one. A PN may also carry up to three component GROUPS separated by =, for alphabetic, ideographic and phonetic renderings of the same name.

DA - a date is eight digits, with no punctuation

YYYYMMDD 20260906

Not 2026-09-06. The older YYYY.MM.DD form appears in files written against ACR-NEMA and is still met in the wild.

TM - a time, with as much precision as was available

HHMMSS.FFFFFF 093015.123456

Everything after the hours is optional, so 09, 0930 and 093015 are all valid times. The fraction is up to six digits.

DT - a date and time in one value, optionally with an offset

YYYYMMDDHHMMSS.FFFFFF&ZZXX 20260906093015.000000+0100

The same rule applies: it may stop at any point, so a DT of 2026 is a valid year. The offset is + or - followed by hours and minutes.

Value multiplicity is not a length

A VM of 1-n means the value may repeat, separated by \ - not that the string may be long. 3 means exactly three, which is why an ImagePositionPatient with two numbers in it is malformed rather than merely unusual.