it's usually the 14th day of your cycle. day 1 is the first day of your period. so first day you bleed, start counting 14 days. Or mid cycle, ex; if your cycle is 32 days, you are likely to ovulate on or around day 16. There are ovulation prediction test very cheap that you can test, just like pregnancy test with urine and will tell you if you are or will be ovulating withing 72 hour window. and last ovulation app that can monitor your menstrual cycle and let you know exactly when you are ovulating. hope this helps!