Cycle
Ovulation
Predict
History
Private
Next Period
Ovulation
Cycle Stats
Avg Cycle: 28 days
Avg Period: 5 days
How Cycle Tracking Works
Understanding your cycle helps you anticipate symptoms, plan ahead, and recognize what's normal for your body. This tracker uses the calendar method: ovulation occurs about 14 days before your next period (adjustable luteal phase). The fertile window spans the 5 days before ovulation plus ovulation day.
- Data privacy: All information is stored only on your device. No account, no cloud.
- Prediction: Based on average cycle length and luteal phase (default 14 days).
Cycle Tracking FAQ
Calendar method is about 75-85% accurate for typical cycles. For conception or avoidance, combine with ovulation tests or basal body temperature.
The tracker uses your average cycle length. For highly irregular cycles, predictions may be less accurate. Track a few months for better averages.
Yes. Data is stored in your browser's local storage. Clearing browser data will erase it. We never see your information.
The time between ovulation and your next period. It's usually consistent for each person (10-16 days). Default is 14.