A starting point for your daily record
Luteal phase calculator
The luteal phase is the time between ovulation (when an egg is released) and your next period. PMDD symptoms can show up then as hormone levels change. These dates give you a rough guide. A daily record shows your own pattern. Read how PMDD is diagnosed.
These are estimates from averages, not a medical test. Do not use this to prevent or plan pregnancy.
Your estimated dates
Cycles can vary. These dates cannot tell you if you have PMDD or PMS. Most premenstrual symptoms show up in the last 7 days before a period.
On a phone, scroll inside the table to see all dates.
| Cycle | Estimated ovulation | Luteal phase | Most likely PMDD/PMS days | Next period start |
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How the math works
Next period start = last period start + cycle length. Add the cycle length again for each later cycle.
Estimated ovulation day = next period start − luteal phase length.
Luteal phase = the day after estimated ovulation through the day before the next period.
Most likely PMDD/PMS days = the last 7 days before the next period.
If your last period was one or more cycles ago, we add full cycles to find the current estimated cycle. This does not confirm that a period happened.