Formating custom dates and comparing dates with different formats

[OmniBlue]

I have two "date" columns in my spreadsheet, and my goal is to compare the two dates for each record and flag those that are not equal:
=if(A1=B1, 0, 1). The problem is that the formats of the "date" columns are different, and Excel does not appear to recognize one of those columns as dates.

Specifically:

Column A: The format is dd-mmm-yy, and Excel seems to recognize these as dates because, when I click on a cell, it is displayed above as m/dd/yyyy.

Column B: The format for these cells was General, initially. I attempted to change this to a date format by selecting those cells --> Format Cells --> Custom --> then entered yyyymmdd, as this is the way that the date is represented in this field. However, Excel still does not seem to recognize these as dates, because when clicking on those cells, they are not displayed above as m/dd/yyyy. And the If formula noted above does not give correct results: It will indicate that two dates are different, when they are not.

What must be done in order in order correctly represent the cells in Column B as dates so that they can be compared to the cells in Column A?

Thank you!!!

[benishiryo]

hi OmniBlue. could you select the both column A & B, then press CTRL + SHIFT + ~
you should see all of them become numbers if they are real dates. Undo it to revert to normal. if they are all numbers, you can simply right-click & format cells to whatever format you want

if they are not, select the range which are not recognized (i guess it's column B). go to Data -> Text to Column -> Delimited -> Next -> Next -> Date: ymd -> Finish. you can formatting of cells mentioned or compare.

if you want to do a formula to compare directly, try:
=IF(A1=--TEXT(B1,"00-00-00"),1,0)
or just:
=--(A1=--TEXT(B1,"00-00-00"))

[OmniBlue]

Thank you so much, benishiryo! Your solution worked perfectly!