Luteal Phase Calculator
Understand your luteal phase length & symptoms
The luteal phase (also called the luteal menstrual phase, or sometimes loosely the "luteinizing phase") is the second half of your menstrual cycle — the time between ovulation and the start of your next period.
After ovulation, the ruptured follicle becomes the corpus luteum, which releases progesterone to prepare the uterine lining for a possible pregnancy. If no fertilized egg implants, the corpus luteum breaks down, progesterone drops, and menstruation begins.
A typical luteal phase lasts 12–14 days and, unlike the follicular phase, stays fairly consistent from cycle to cycle for most women.
Rising then falling progesterone during the luteal phase commonly causes:
These two overlap heavily — which is exactly why the wait can feel confusing. Here's how they compare:
The only certain way to tell the difference is a pregnancy test taken after your missed period (or ~14 days past ovulation) for an accurate result.
