Tsuki Period Diary

Get to know your body, one cycle at a time. Tsuki is a personal period tracking tool — not a medical device and not intended to diagnose medical conditions. 🔒 Fully offline. No account, no ads — your data stays on your phone. 🗓 Cycle Tracking & Reminders • Log your period with one tap and get predictions for your next period, ovulation and fertile window • Reminders before your period and when your fertile window begins • For irregular cycles, predictions are shown as date ranges and "period is late" alerts are paused to avoid unnecessary anxiety 📝 Daily Logging • Log symptoms, mood, discharge, spotting and pain relievers with a simple tap • Personalized PMS alerts based on patterns in your own history • Daily health tips based on your current cycle phase 🩺 Three Modes + Pregnancy Mode • Track / Conceive / Avoid Pregnancy — switch modes anytime • During pregnancy, pause predictions and reminders. They automatically resume after you log your first postpartum period ⚠️ Avoid Pregnancy mode is a statistical aid and is not a medical contraceptive method. 📊 Stats & Doctor Report • Cycle regularity, average cycle length, period length and symptom frequency • Export a PDF cycle report to share with your gynecologist 📚 Learning Center • Six chapters about periods and body care, designed for girls ages 9–12 📁 Backup & Restore • Export and import your data in JSON format — your data stays under your control 🔓 Premium • BBT logging and chart • LH test logging and detailed discharge categories (Billings method) • Fertility score (BBT temperature shift + discharge + LH) • Personalized higher-chance days for Avoid Pregnancy mode (Ogino method, requires 6 cycles) • Unlimited cycle trend charts (free version: last 12 cycles)