Period Calculator — Next Period Date
The Period Calculator predicts how many days until your next menstrual period based on the start date of your last period and the average length of your cycle. Most cycles range from 21 to 35 days, with 28 days being the average. Use this tool to plan ahead, track your cycle, and stay prepared.
Frequently Asked Questions
This calculator is based on average cycle length and provides an estimate. Actual periods can vary by a few days due to stress, illness, weight changes, or hormonal fluctuations.