When is my next period due?
See when your next period may start, shown as a range from your own cycle length. Works for irregular cycles too. No sign-up.
Tap the day your last period started
Not sure? Pick your best guess. You can change it any time.
November 2026
Common questions
How is my next period estimated?
femio starts from the first day of your last period and adds your cycle length. Because cycles shift, it shows a window that reflects how much your own cycles vary, not one date.
Is a period a few days late normal?
Cycles shift by a few days for many ordinary reasons, which is why you see a range and no “late” counter. If your period has not come and you could be pregnant, a test is the first step. If about three months pass with no period, talk to a clinician.
What if my cycle changes every month?
Choose “Irregular / not sure” and enter your shortest and longest cycles, and the window widens to match. If your cycles vary too much, femio says there is no confident window rather than guessing. If your cycles are often irregular, it is reasonable to mention it to a clinician.
These calculators give general estimates for learning and planning, not medical advice. Talk to your clinician about your health.