Hello and thanks you all for the kind suggestions that helped me a lot.. I have found some points: -first of all, I don't now why but I had to use "." instead of ":" as separator for time.. 15:30 won't be accepted while 15.30 is ok... this even if cells were formatted as time maybe this is due to my regional settings -for the circular reference mentioned by Brian Barker it was a mistake copying the formula from the sheet to the webpage.. sorry for this.. Anyway, changing the separator works fine -when I have: E14: 23/04/15 15.30 E15: 25/04/15 16.20 both E16: =E15-E14 and E16 = DAYS(E15;E14) give the integer number 2.0 but using the first formula and changing format to hours and back to numbers I have 2.034 that should be correct.. thanks again! -- View this message in context: http://nabble.documentfoundation.org/time-and-date-difference-tp4147099p4147106.html Sent from the Users mailing list archive at Nabble.com. -- To unsubscribe e-mail to: users+unsubscribe@global.libreoffice.org Problems? http://www.libreoffice.org/get-help/mailing-lists/how-to-unsubscribe/ Posting guidelines + more: http://wiki.documentfoundation.org/Netiquette List archive: http://listarchives.libreoffice.org/global/users/ All messages sent to this list will be publicly archived and cannot be deleted