Check out the formulas in this thread.
I think this is what you are looking for.
Hope this helps in answering your query
2 of 2 people found this helpful
Your EPOCH is too long. At the time of writing this, the current EPOCH is 1464277281 according to http://www.epochconverter.com/.
That's a 10 digit EPOCH.
Your sample EPOCH is 1464170400000 which is 13 digits long, no wonder your time is huge!
Either fix the source, or change your formula to take only the left 10 digits from the epoch; DATE(DATEADD('second', INT(left(str([Epoch Time stamp(GMT)]),10)), DATE("1970-01-01")))
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