In calc is there a formula to show what day of the week my birthday will be on this year?
And what day of the week I was born on?
Well, don’t know about your birthday, but for my birthday - LO lacks a function BIRTHDAY_OF_MIKE_KAGANSKI 
- must be an oversight.
Seriously - you seem to need WEEKDAY function.
Thanks! It worked great for what day of the week I was born on. Not sure how to use it to know what day of the week my birthday will be on this year.
=WEEKDAY("2018-01-04") ; =WEEKDAY(DATE(2018;01;04))
Thanks Mike. Got it I think. it returns the day of the week. I just can’t get it to look ahead! if my birthday is March 30 1952, what day of the week will it be this year? I can’t get a cell to take my birthday, and then to add up 66 years, to say March 30 2018, so that the format of that cell to say the day of the week for 2018. Thanks for your time and thought. Have a great day.
If A1 contains March 30 1952, in B1 is Jan 31 2018, then you can do in C1: =WEEKDAY(DATE(YEAR(B1);MONTH(A1);DAY(A1)))
If in B1 you have 66 instead, then you can do =WEEKDAY(DATE(YEAR(A1)+B1;MONTH(A1);DAY(A1)))
IT WORKED! Thanks! It worked for all 33 of family and relatives birthdays. Not a must, just enjoy such, as you. Again, have a great day.
One last but a different question I think you may know what i should do. I have a calc fill 955kb size that I use daily, I’ve had it for 2 years, (26 tabs, to many?). At times, (the last 8 months or so), it will have random errors, I hit F9 and every time it fixes it. Is it something that I should worry about? Or an easy fix? Or do you know who I should ask, if it is even something that should be fixed, seeing it is something I did while building it, and now ok with it?
That should be opened as a new question rather than including it here.
Also please do not post as community wiki (although my answer is an exception). See guidelines for asking.
OK. this is my first time here. Thanks
I read it, I do not know how to “mark this as correct”! Or am I to mark it? There was a wiki box, not knowing what that was, I thought it best to mark what was asked of me. Sorry about that, I should of read guidelines first. Also not understanding the statement, (although my answer is an exception). It just was all mystical to me. But was a real help. Hope I did not offend anyone. Thanks for the help.
“I do not know how to mark this as correct” - click on 
as shown in the first image in the “mark this as correct” link in the answer.
“Also not understanding the statement, (although my answer is an exception).” - What I meant is that although normally we don’t use the wiki checkbox, I did use it for the answer because the information is not mine but rather @mikekaganski’s, so I did not want to take undue credit.
Thanks Jim! It’s getting a little clearer to me.
From the comment by @mikekaganski
If A1 contains March 30 1952 and in B1 is Jan 31 2018, then in C1:
=WEEKDAY(DATE(YEAR(B1);MONTH(A1);DAY(A1)))
If in B1 you have 66 instead, then you can do:
=WEEKDAY(DATE(YEAR(A1)+B1;MONTH(A1);DAY(A1)))
Please mark this as correct to close out the question. -Jim K