buncha/health & fitness/period

Period Tracker

Your data stays on this device. Periods are saved to this browser's local storage only — no account, no upload, no analytics on the entries themselves. Export a CSV any time to take it with you, or clear everything in one click.

Start by logging your last period. Pick the start date and approximate duration. After 2+ entries we can start predicting cycle length and your next period.

Log a period

Start date

Duration (days)

Flow (optional)

Notes (optional)

This is a tracker, not a diagnostic tool. Cycle predictions are based on averages of your logged data and textbook luteal-phase length (~14 days before the next period). Real cycles vary widely. If predictions feel off, log more cycles — accuracy improves with data. For pregnancy planning, contraception decisions, or any concerning symptoms, talk to a clinician.

Read the guide

A Period Tracker That Stays on Your Phone

Pairs well with

Ovulation Calculator

Track your menstrual cycle, predict fertile window…

About Period Tracker

Log periods month-over-month. Cycle history, average length, next-period prediction, current phase. Stays on your device.

Like every tool on Buncha, this one runs entirely in your browser. There's no upload, no log, no record of what you've pasted or generated. Close the tab and the data is gone.

↳ Have feedback or found a bug? hello@buncha.tools