Formula to convert days into months

[FAUK05]

Hi,

I want to convert total days into months with a formula.
More specifically 10 oct 1982 - 1 nov 1982 = 22 days ; How many months is this? And what is the formula?

I researched many formula's but they round up the months into 30 days or 360days.

Thank you in advance for your help.

 

[ParamRay]

You must assume a month is a fixed number of days.

If you want maximum precision:
- Every 400 years there are exactly 4,800 months.
- Every 400 years there are exactly 146,097 days.

Therefore a month contains 146,097 ÷ 4,800 = 30.436875 days.

So, in the example you gave, 22 days = 22 ÷ 30.436875 = 0.722807449844966 months.

 

[sheetspread]

Datedif returns integers rounded down:

Excel 2010
	A	B	C
1	10/10/1982	11/1/1982	0
Sheet6

Cell Formulas
Range	Formula
C1	=DATEDIF(A1,B1,"m")

 

[FAUK05]

Thank you,

This is accurate yes.
Now my problem is that i have start dates in column A en end dates in column B.
Sometimes the calculation between the dates are 365 days and sometimes it's less than a month (22 days more or less).
If i use the formula u gave me i get 11.99 months when days are 365.

I want a formula that calculates start date and end date in column C en months in cell D.
Where if total date is less then the actual days for that month it should stay per example 0.722 months.
But when 365 days it should be 12 month. And 387 days would be 12.722 months

 

[FAUK05]

Hi All,

I have found a formula that fits my needs:

A1 16 feb 1982
B2 28 feb 1983

Formula (B2-A1)/(365/12)