Calcolatrice ciclo mestruale
The detailed guide below is currently available in English.
How cycle prediction works
A cycle is counted from the first day of one period to the first day of the next, averaging 28 days but normally ranging from 21 to 35 or so. The calculator projects forward in equal steps of your average cycle length and estimates ovulation about 14 days before each following period, with the fertile window spanning the five days before ovulation plus the day after. Bleeding days are laid out from your typical period length.
When tracking becomes useful for health
Beyond planning, a record of cycle dates is genuinely medical information. Bring it to appointments: cycle length trends, missed periods, bleeding between periods, or pain that disrupts normal life can point to conditions worth evaluating, from thyroid shifts to polycystic ovary syndrome and endometriosis. Apps and paper both work — what matters is the pattern over several months. This calculator is informational and not a substitute for medical care.
Domande frequenti
How accurate are period predictions?
For regular cycles, the first projected month is usually close — within a few days. Accuracy fades further out because natural variation compounds, so treat cycle 2 and 3 dates as planning sketches rather than appointments.
What counts as an irregular cycle?
Cycles that swing more than about 7–9 days between the shortest and longest over several months are generally considered irregular. Occasional variation is normal; a sudden persistent change, very heavy bleeding, or gaps beyond 35–40 days warrant medical advice.