Period Calculator
Results
Enter your dates and select Calculate to see predictions.
Next period
Ovulation estimateNot a confirmed ovulation date
PeriodFertile windowOvulation
Cycle timeline
Day 1
Future periods
| Cycle | Period dates | Fertile days |
|---|
Estimates assume consistent cycles. Ovulation is estimated approximately 14 days before the next period; fertile days are an approximation. Do not use this calculator for contraception or pregnancy diagnosis. Irregular cycles can make predictions unreliable.