Ovulation & Fertility Calculator

Estimate your fertile window and ovulation day based on your cycle length. Track your most fertile days for the next 6 cycles.

Average is 28 days

Signs of Ovulation

  • Rise in basal body temperature (0.5-1°F after ovulation)
  • Change in cervical mucus (clear, stretchy, egg-white consistency)
  • Mild cramping or twinge on one side (mittelschmerz)
  • Breast tenderness
  • Increased sex drive
  • Positive ovulation predictor kit (OPK) test
  • Light spotting
  • Heightened sense of smell

Fertility Tips

  • Have intercourse every 1-2 days during the fertile window for best chances
  • The most fertile days are the 2-3 days before ovulation and ovulation day itself
  • Sperm can survive up to 5 days in the reproductive tract, but the egg only survives 12-24 hours
  • Tracking basal body temperature can confirm ovulation but can't predict it in advance
  • Ovulation predictor kits (OPKs) detect the LH surge 24-36 hours before ovulation
  • Stress, illness, and travel can shift ovulation timing even with regular cycles