Missed Period Calculator

A period that has not arrived on its expected date can prompt concern, but late periods are extremely common and have many causes that have nothing to do with pregnancy. This calculator takes your last period start date and average cycle length, computes the date your next period was expected to arrive, and tells you precisely how many days late it currently is — or how many days remain until it is expected if it has not yet arrived. A period that is 1–7 days late falls within a range that is very common and often explained by minor fluctuations in ovulation timing, stress, illness, or changes in routine. A period that is 8–14 days late is worth noting, though still frequently caused by non-pregnancy factors. A period more than two weeks late is generally recommended to be discussed with a healthcare provider. This calculator does not assess pregnancy, hormonal conditions, or any medical cause for a late period. It is a date-arithmetic tool only and is intended purely for informational awareness. Always consult a qualified healthcare provider for persistent changes to your cycle or if you have additional symptoms alongside a missed period.

The expected period date is calculated by adding your average cycle length in days to the start date of your last period. The number of days late is the difference in days between today's date and that expected date. A negative result means the period has not yet reached its expected date. Status thresholds are: not late (0 or fewer days), slightly late (1–7 days), late (8–14 days), and significantly late (15+ days). These thresholds are general reference points and not clinical criteria. Many factors beyond pregnancy — stress, illness, and lifestyle changes — commonly shift ovulation and therefore period timing by several days or more.