Period Calculator
Predict the date of your next few periods.
Result
Results are estimates for general information only and are not professional advice.
Predicting your period
By adding your cycle length to the first day of your last period, this calculator estimates the start dates of your next three periods, helping you plan ahead.
Frequently Asked Questions
What is the Period Calculator?
Predict the date of your next few periods. It runs instantly in your browser and is completely free.
Is the Period Calculator free and does it require signup?
Yes. Every calculator on Calculatis is 100% free with no registration, and the values you enter are never stored.
How accurate is the Period Calculator?
It uses standard, widely-accepted formulas. Results are reliable estimates for general use and are not a substitute for professional advice.