Period Calculator
Track your menstrual cycle and predict future periods, ovulation, and fertile windows.
Calendar Legend
Next Period Expected
Sun, Jul 5, 2026
Average cycle length (days)
28 days
Regular
Cycle Regularity
Upcoming Periods
Sun, Jul 5, 2026
Cycle 1
Sun, Aug 2, 2026
Cycle 2
Sun, Aug 30, 2026
Cycle 3
Sun, Sep 27, 2026
Cycle 4
Sun, Oct 25, 2026
Cycle 5
Sun, Nov 22, 2026
Cycle 6
Fertile Windows & Ovulation
Jun 16 - Jun 22
Ovulation: Jun 21
Cycle 1
Jul 14 - Jul 20
Ovulation: Jul 19
Cycle 2
Aug 11 - Aug 17
Ovulation: Aug 16
Cycle 3
Sep 8 - Sep 14
Ovulation: Sep 13
Cycle 4
Oct 6 - Oct 12
Ovulation: Oct 11
Cycle 5
Nov 3 - Nov 9
Ovulation: Nov 8
Cycle 6
Understanding Your Cycle
A typical menstrual cycle lasts 21-35 days. The cycle has four phases: menstruation (days 1-5), follicular phase (days 1-13), ovulation (day 14), and luteal phase (days 15-28). Tracking helps identify patterns.
Benefits of Tracking
Period tracking helps you prepare for your period, identify irregular cycles, optimize conception timing if trying to conceive, and notice health changes to discuss with your doctor.
When to See a Doctor
Consult a healthcare provider if your cycle is consistently shorter than 21 days or longer than 35 days, you miss periods, have very heavy bleeding, or experience severe pain.