Menstrual Cycle Predictor
Predict the next 6 expected period start dates from a recent period and cycle length. Not medical advice.
Result
Next period start
2026-05-29
28-day cycle.
- Cycle +12026-05-29
- Cycle +22026-06-26
- Cycle +32026-07-24
- Cycle +42026-08-21
- Cycle +52026-09-18
- Cycle +62026-10-16
Step-by-step
- Each next period = previous start + 28 days.
- Next 6 expected dates listed in breakdown.
How to use this calculator
- Enter last period start.
- Enter average cycle length.
- See next 6 expected dates.
About this calculator
Predicts upcoming period start dates assuming a constant cycle length. Average cycle is 28 days; normal range is 21-35. For irregular cycles use the average over 3-6 months. Not medical advice.
Frequently asked
28 days is the textbook average. Real-world: 21-35 days is normal. Outside that range, consult a provider.
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