Calculate Your Fertile Window

Calculating your fertile window

The fertile window is the short period during which pregnancy is possible. It usually lasts 5 to 6 days per cycle.

It includes the days before ovulation and the day of ovulation. Sperm can live up to 5 days, while the egg is viable for about 24 hours.

With regular cycles, ovulation happens about 14 days before the next period. It is not always day 14 of the cycle, but 14 days before the next bleed.

For example, in a 28‑day cycle, ovulation is around day 14 and the fertile window is roughly days 10 to 15.

Your body can give clues: clearer, stretchy discharge, slight lower‑belly discomfort, or higher energy.

With irregular cycles, calculating is harder. Tracking over several months or talking to a professional can help.

Knowing your fertile window helps whether you are trying to conceive or simply track your cycle.