If I have a 32 day cycle and my cycle started dec 31 and ended jan 4, when will I ovulate, and when should I start using my ovulation kit?

18 days. 32 day cycle-you ovulate approximately on day 18 with day 1 as the first day of your period.
Day 18. Ovulation typically occurs about 14 days before your period begins. If you consistently have 32 day cycles, you probably ovulate around day 18, where day 1 is the first day of your period. So, in this case, day 1 is dec 31, and day 18 will be on jan 17. You should begin testing a few days before that, so tomorrow would be a good time. Good luck.