Abbreviation of Doctor of Philosophy: PhD or DPhil? I am a bit confused about the proper abbreviation of Doctor of Philosophy. I sometimes read that this person obtained his D.Phil from X University, while someone else obtained his PhD from Y University. According to Wikipidia:


  The University of Oxford also abbreviates their Doctor of Philosophy degree as DPhil but in other respects is equivalent to a PhD.


Is it up to me to decide what abbreviation to use?
The awarding institution determines the abbreviation*; someone made a Doctor of Philosophy at Oxford is a DPhil, someone made a Doctor of Philosophy at Cambridge is a PhD, and someone made a Doctor of Philosophy at a university in Austria is a Dr.phil. (before the name, not after).

*At the time awarded, as pointed out in another answer.

Addendum: As Jack Orion points out, the abbreviation is of the Latin doctor philosophiae, which is why appears both ways around (Latin is more flexible in its word order than English). Many other degree abbreviations make their Latin origin more obvious (e.g. the MLitt for 'master of letters', magister litterarum; the LLB for 'batchelor of laws', legium baccalaureatus, with conventional doubling of the 'L' to indicate the plural).