Find your fertile window and ovulation day in seconds
Cycle Info
Typical range: 21–35 days
Most people: 12–14 days
Today's Cycle Phase
Fertile Window
Day 15 of your cycle
Fertile Window
Fri, June 19, 2026
through
Thu, June 25, 2026
Active now
Ovulation Day
Wed, June 24, 2026
1 day ago
Additional Dates
Next Period (estimated)
Thu, July 9, 2026
14 days away
Luteal Phase Starts
Thu, June 25, 2026
Day 15 – Day 28 of cycle
Cycle Timeline
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This calculator provides estimates based on average cycle patterns. Individual cycles vary. These results are for informational purposes only and should not replace professional medical advice.
Our free ovulation calculator estimates your fertile window and predicted ovulation day based on the first day of your last menstrual period and your average cycle length. Whether you are trying to conceive or simply want to understand your cycle better, knowing when you ovulate helps you make informed decisions. Results update instantly — no account required.
Ovulation typically occurs 14 days before your next expected period — in other words, on day (cycle length minus 14) of your cycle. For a standard 28-day cycle that places ovulation on day 14. If your cycle is longer or shorter, this tool adjusts the date accordingly.
The fertile window spans about 6 days: the 5 days before ovulation plus ovulation day itself. Sperm can survive in the reproductive tract for up to 5 days, while an egg lives only 12–24 hours after ovulation. Having intercourse during this window gives the best chance of conception.
The luteal phase is the second half of your cycle, starting the day after ovulation and ending when your next period begins. It typically lasts 12–14 days and is the phase when a fertilized egg may implant. An unusually short luteal phase can sometimes affect fertility.
This tool provides a statistical estimate based on averages. Actual ovulation can vary due to stress, illness, travel, or hormonal fluctuations. For precise tracking, combine these estimates with basal body temperature (BBT) charting, ovulation predictor kits (OPKs), or consultation with a healthcare provider.