?B?dmlvbGFzcmJlc3Q=?= wrote

I want to shade a cell if the date shown is not a weekday. I know I
need to use conditional formatting, but I can't work out what formula
to use.

You say "the date", but if you have a column or row of dates, select them
all and apply Formula Is:

If column A
=WEEKDAY($A1,2)=6
If row 1
=WEEKDAY(A$1,2)=6

Choose desired format

--
David