1
Cycle Day
Menstrual
28
Days Until Next
predicted
28
Avg Cycle
days
5
Avg Period
days
Today's Flow
How is your flow today?
Symptoms Today
Tap to add or remove
Mood
One word for how you feel right now
Gentle Reminder
Your body is not a problem to solve. It is a rhythm to honor.
Your Cycle
based on your last period-
Next Period
in - days
-
Ovulation
estimated
-
Fertile Window
estimated
-
Current Phase
3-Month View
colored by cycle phaseMenstrual
Follicular
Ovulatory
Luteal
Log Today's Flow
Cramping level (1 gentle - 5 strong)
Flow History
last 30 daysRecent Entries
Symptom Library
tap to log today30-Day Frequency
how often each symptom showed upPMS Journal
Self-Care Rituals
Tap what helped today
Trigger Notes
What made things harder today?
What Helped - Tag History
patterns of relief across cycles
0
Periods Logged
-
Avg Cycle
days
-
Avg Period
days
-
Prediction
accuracy
Cycle Length Trend
last 6 cyclesPeriod Log
About PeriodOS
PeriodOS is a private, offline period tracker. Every entry lives in your browser. Nothing is sent anywhere. Nothing is shared. Your cycle, your data, your body.
Data
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