You can also check ovulation calculator on www.babymed.com... Have used it both for calculations and baby sex selections and it has always worked for me. Key is knowing the number of cycle days you have.

Hello Nnadozie, it requires a lot of explanation but I'll summarize. Ovulation day calculation is easy and possible only when the menstrual cycle is regular (e.g 28 days). So the ovulation is at mid cycle, i.e day 14. There are other signs, slightly raised body temperature, slimy vaginal fluid, full breast and sometimes high libido. Ovulation kits available in pharmacy and Android apps also help. Cheers.