Use our free period calculator online to track your cycle, predict your next date, and understand your body — all in one calm, private place.
Enter your last period date and average cycle length to get started.
These are estimates based on an average cycle. Results may vary. This tool is not a substitute for medical advice.
Built with care, backed by science, designed for real life.
Accurate next-period forecasting based on your personal cycle length — not a generic 28-day assumption.
Know your most fertile days and ovulation date so you can plan — whether you're trying to conceive or not.
All calculations happen in your browser. We store nothing. No account, no tracking, no data sharing. Ever.
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