Period
Calculator

Predict upcoming menstrual periods, ovulation dates, and fertile windows based on cycle length and last period date.

Cycle Settings

days
days

Next Period

Apr 17, 2026

Current Cycle Day

Day 1

Legend

PeriodMenstruation days
OvulationEstimated ovulation
FertileFertile window

Predictions

CyclePeriod StartPeriod EndOvulationFertile Window
#1Apr 17, 2026Apr 21, 2026May 1, 2026Apr 26, 2026 - May 1, 2026
#2May 15, 2026May 19, 2026May 29, 2026May 24, 2026 - May 29, 2026
#3Jun 12, 2026Jun 16, 2026Jun 26, 2026Jun 21, 2026 - Jun 26, 2026
#4Jul 10, 2026Jul 14, 2026Jul 24, 2026Jul 19, 2026 - Jul 24, 2026
#5Aug 7, 2026Aug 11, 2026Aug 21, 2026Aug 16, 2026 - Aug 21, 2026
#6Sep 4, 2026Sep 8, 2026Sep 18, 2026Sep 13, 2026 - Sep 18, 2026

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