On every Membership transaction, there is an Exp Date that can be used to determine when that specific transaction will expire. You will also find a column on the Membership grid called, “# of days until expiration”. This column can be helpful if you don’t wish to filter by a specific date range but rather everyone who expires within a certain number of days.
While looking at the Exp. Date, it might be worth also paying attention to the Current Expiration Date column. If you see a different date listed there, this means this Constituent has a newer Membership transaction with a different expiration date that is farther into the future.