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QUESTION: Hi Tom

I need a spreadsheet that will calculate hours worked from start and finish times, eg I would like to enter a start time of 8am, finish time 4.30pm with 30 mins for lunch and arrive at a total hours worked of 8 hours worked. I have tried to format the cells as time, but it isnt working. Do you know a good way to do this?

ANSWER:

a1: 8:00 AM

B1: 4:30 PM

C1: =B1-A1-time(0,30,0)

custom format C1 as hh:mm or h:mm

and it will display 8:00

if you don't want to show minutes then custom number format a h

if you actually want the number 8 stored in the cell then format it as general and change the formula to

=(B1-A1-time(0,30,0))*24

time is stored as the fraction of a day. If you wanted to enter 8 AM as the way it was stored you would put in

.333333333333333

for noon

.5

if you then format those cells at Time, they will appear as 8:00 or 8:00 AM depending on how you format it. (or for noon)

and so forth.

to convert .333333333333333 to be 8 hours, multiply it by 24

=.333333333333333 * 24 = 8

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Regards,

Tom Ogilvy

---------- FOLLOW-UP ----------

QUESTION: The first option is working fine, thanks very much. I now need to sum the hours worked each day, but I am getting a strange result. 4 days at 8 hours should sum to 32hours, but I am getting 8 hours? Can you help me with this? I have formatted the total cell the same as the others, ie H:MM.

Thanks

Gail

Gail,

format the total cell as [h]:mm

Time is really stored as a date - so it is Date/Time

the number stored is the number of days from a base date (Midnight of Dec 31, 1899; i.e. beginning of 1900. So 2 January 1900 as noon would be 1.5: 1 and 1/2 day.

when you add up your times and they result in a number larger than 24, excel sees that as 8 AM on 2 January. So it only shows the 8 hours. when you enclose the h in brackets, it tells excel to show total hours and not treat the value as a data and time, but only as a time.

--

Regards,

Tom Ogilvy

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