8. Print 90000 five-digit numbers
$$
10000,10001, \cdots, 99999
$$

on cards, with one five-digit number on each card. Some cards (such as 19806, which reads 90861 when flipped) have numbers that can be read in two different ways, causing confusion. The number of cards that will not cause confusion is $\qquad$ cards.
8. 88060 .
Among the ten digits $0 \sim 9$, the digits that can still represent numbers when inverted are $0, 1, 6, 8, 9$.

Since the first digit cannot be 0 and the last digit cannot be 0, the number of such five-digit numbers that can be read when inverted is $4 \times 5 \times 5 \times 5 \times 4=2000$.

Among these 2000 five-digit numbers, we need to exclude the five-digit numbers that do not cause confusion when read backwards (such as 10801, 60809).
Now, divide the digits of the five-digit number into three groups.
【First Group】The first and last digits form a group with four possibilities: $(1,1),(8,8),(6,9),(9,6)$;
【Second Group】The second and fourth digits form a group with five possibilities:
$(0,0),(1,1),(8,8),(6,9),(9,6)$;
【Third Group】The third digit can be $0, 1, 8$ three possibilities.
Thus, the number of five-digit numbers that read the same forwards and backwards is $4 \times 5 \times 3 = 60$.
Therefore, the number of five-digit numbers that do not cause confusion is $90000-(2000-60)=88060$ (numbers).