The DATEVALUE function is to convert a date from text format to a serial number.
Formula:
=DATEVALUE(date_text)
Explanations:
The date_text is required, which is a date in text format, e.g., "2001/2/4".
Cautions:
The dates in Excel are stored the sequential serial numbers and can only be a date between January 1, 1900 and December 31, 9999.