Ovulation Calculator

Estimate your fertile window and ovulation date based on your cycle.

First Day of Last Period

Average Cycle Length (days)

Understanding Ovulation

Ovulation typically occurs about 14 days before the start of the next period. The fertile window spans 5 days before ovulation and 1 day after. Sperm can survive up to 5 days, while an egg is viable for 12-24 hours after release. This is an estimate — actual ovulation varies.