Period Tracker & Next Period Calculator

Enter the first day of your last period and your usual cycle length, and we will estimate your next three periods. Over time, tracking helps you see your own pattern.

Your next three periods (estimated)

Educational, not medical advice. These are estimates based on a regular cycle. Real cycles vary from month to month, so treat this as a guide. It runs in your browser and stores nothing.

When to see a doctor

See a doctor for periods that suddenly become very irregular, very heavy, very painful, or that stop for three months or more when you are not pregnant. These are worth checking, not worrying about alone.

Go further

The Trying-to-Conceive Blueprint

A private community for women trying to conceive, honest guidance, and a professional to ask.

See the program →