It depends on which month and day she is born on in 1975.
If you want it from todays current date, she would be 46.
If her birthday is the 11 / 04 / 1975 (eleventh of April) - 31 / 12 / 1975 (thirty-first of December) then she is 45 years old. If her birthday has already passed in 2021 she is 46.
