Converting unix time into date-time via excel

Question

Trying to convert 1504865618099.00 Unix time into a readable date time. I tried this:

=(UNIX + (\"1/1/1970\"-\"1/1/1900\"+1)*86400) / 86400

Answer 1

=A1/(24*60*60) + DATE(1970;1;1) should work with seconds.

=(A1/86400/1000)+25569 if your time is in milliseconds, so dividing by 1000 gives use the correct date

Don't forget to set the type to Date on your output cell. I tried it with this date: 1504865618099 which is equal to 8-09-17 10:13.