Ovulation Calculator

Predict your most fertile days and ovulation date based on menstrual cycle length to optimize conception chances.

Free to use
12,500+ users
Updated January 2025
Instant results

Ovulation Calculator

Fertility & cycle tracker

Track Your Fertile Window

This calculator predicts your most fertile days based on your menstrual cycle. Ovulation typically occurs 14 days before your next period.

Your Cycle Information

When did your last period start?

Normal range: 21-35 days (average is 28)

How many days does your period typically last?

Signs of Ovulation

Cervical Mucus Changes

Clear, stretchy, egg-white consistency

Basal Body Temperature

Slight temperature rise (0.5-1°F) after ovulation

Increased Sex Drive

Natural libido boost during fertile window

Mild Cramping

Brief, one-sided pain (mittelschmerz)

Tips for Conception

Time It Right

Have intercourse every 1-2 days during fertile window

Track Your Cycle

Monitor for at least 3 months for accurate predictions

Healthy Lifestyle

Maintain healthy weight, reduce stress, avoid smoking

Check Ovulation Signs

Monitor cervical mucus and basal body temperature

Understanding Your Menstrual Cycle

1. Menstruation (Days 1-5):

Shedding of uterine lining. Hormone levels are low. This is Day 1 of your cycle.

2. Follicular Phase (Days 1-13):

Follicles develop in ovaries. Estrogen rises, preparing uterus for potential pregnancy.

3. Ovulation (Day 14):

Mature egg released from ovary. Peak fertility. Egg survives 12-24 hours.

4. Luteal Phase (Days 15-28):

Progesterone rises to prepare uterus. If no pregnancy, hormone levels drop and period begins.

Note: Cycle lengths vary between individuals. Track for 3+ cycles for better accuracy. Consult a healthcare provider if cycles are very irregular or if trying to conceive for over a year.

Important Note

This calculator provides estimates based on average cycles. For irregular cycles, fertility concerns, or family planning, consult with a healthcare provider. Not intended as birth control method.