Period Calculator
Track your menstrual cycle and predict future periods, ovulation, and fertile windows.
Calendar Legend
Next Period Expected
Fri, Apr 3, 2026
Average cycle length (days)
28 days
Regular
Cycle Regularity
Upcoming Periods
Fri, Apr 3, 2026
Cycle 1
Fri, May 1, 2026
Cycle 2
Fri, May 29, 2026
Cycle 3
Fri, Jun 26, 2026
Cycle 4
Fri, Jul 24, 2026
Cycle 5
Fri, Aug 21, 2026
Cycle 6
Fertile Windows & Ovulation
Mar 15 - Mar 21
Ovulation: Mar 20
Cycle 1
Apr 12 - Apr 18
Ovulation: Apr 17
Cycle 2
May 10 - May 16
Ovulation: May 15
Cycle 3
Jun 7 - Jun 13
Ovulation: Jun 12
Cycle 4
Jul 5 - Jul 11
Ovulation: Jul 10
Cycle 5
Aug 2 - Aug 8
Ovulation: Aug 7
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.