📅 Women's Health

Period Calculator

Predict your next period and track your menstrual cycle over the next 6 months.

Your Cycle

Enter your last period and settings

First day of last period

Cycle length (days)

Period duration (days)

Enter your last period date

Set your cycle length to predict upcoming periods.

What is a normal cycle?

Cycles of 21–45 days are normal. 28 days is average. Variation of 7–9 days each month may indicate irregularity.

Why might my period be late?

Stress, illness, weight changes, intense exercise, or pregnancy can all affect timing.