I am a supporter ofSt. Joseph's hospice. If you find this site useful or if it helped you, consider a small donation toSt. Joseph's, please.
Information onSt. Joseph's
You need a worksheet function to test for overlapping ranges?
If adjacent ranges of time period may touch each other and if you want to see which range overlaps with others:
Note: Please exchange ";" by ","!
In this example you array enter the formula into C2:C6 in one go.
You might prefer the simple Sumproduct formula =REPT("Overlap! ",SUMPRODUCT(--(A2<INDEX(D,,2)),--(INDEX(D,,1)<B2))-1) in C2 which you copy down :-)