Ovulation Calculator

Calculate your ovulation date and fertile window to help with family planning.

Select the first day of your last period
The average menstrual cycle is 28 days, but can range from 21-45 days
The luteal phase is typically 14 days (10-16 days is normal)
Your Ovulation Calendar
Ovulation Date

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Your most fertile day
Fertile Window

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Best days for conception
Next Period Expected

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Approximate date of your next menstrual period
Detailed Fertility Calendar
Phase Dates Description
Conception Probability
Tips for Increasing Conception Chances:
  • Have intercourse every 1-2 days during your fertile window
  • The day before and day of ovulation have the highest conception rates
  • Sperm can survive up to 5 days in the female reproductive tract
  • An egg survives approximately 12-24 hours after ovulation
  • Track your basal body temperature for more accuracy
  • Consider using ovulation predictor kits (OPKs)
About Ovulation

Ovulation is when a mature egg is released from the ovary and becomes available for fertilization. It typically occurs about 14 days before your next period.

Signs of Ovulation:
  • Change in cervical mucus (clear, stretchy, egg-white texture)
  • Slight increase in basal body temperature
  • Mild pelvic or abdominal pain (mittelschmerz)
  • Increased sex drive
  • Breast tenderness
  • Light spotting
Understanding Your Fertile Window

Your fertile window is the 6-day period that includes the 5 days before ovulation and the day of ovulation itself.

Conception Chances by Day:
  • 5 days before: ~10% chance
  • 3 days before: ~15% chance
  • 2 days before: ~25% chance
  • 1 day before: ~30% chance (peak)
  • Ovulation day: ~25% chance
  • 1 day after: ~10% chance
Note: This calculator provides estimates based on average cycle data. Actual ovulation timing can vary. For best results, combine with ovulation test kits or basal body temperature tracking.
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