How the days since your last period are worked out
Menopause is confirmed by 12 consecutive months without a period, which makes counting dates more consequential than it looks. This calculator takes the start date of your last period, reports the days elapsed and the elapsed time in calendar months, and shows the date the 12 months are reached along with the time left to it. Leave the reference date blank and today is used.
Elapsed time is worked out in days first and then converted to calendar months. Adding a month to 31 January lands on a February that has no 31st, so the date is clamped to the last day of that month, and leap years are handled the same way. Future dates, and a reference date earlier than the last period, cannot be calculated and bring up a message instead.
This page does not divide the transition into stages and does not rate symptom severity. Those frameworks are not confirmed in an authoritative source, and no score or grade is produced. If a period returned in between, the 12 months start again from that date, so enter the new one. Current as of October 2026, and not a medical diagnosis. Bleeding after menopause has been confirmed, or a large change in your pattern, should be seen by a clinician.
Frequently Asked Questions
The 12 months start again from scratch, because the confirmation rule is 12 consecutive months without a period. Enter the most recent start date and calculate again.
Because it is worked out in days first and then converted to calendar months. Months differ in length, so the figure rarely lands on a whole month; a week is 7 days and a month is a calendar month here.
Staging frameworks and symptom severity scales are not confirmed in an authoritative source. Assigning a stage on an unconfirmed basis creates needless worry, or needless reassurance, whenever it is wrong. This page works out dates only.