Sleep Cycle Calculator

Sleep Cycle Calculator helps you wake up refreshed by timing your sleep around 90-minute sleep cycles. Pick a wake-up time to see the best bedtimes, or tap "sleep now" to see the best times to wake up — each suggestion shows the cycle count and hours of sleep. FEATURES • Wake-up planner: choose a wake time, get 4 suggested bedtimes (6, 5, 4 and 3 cycles) • Sleep-now planner: get 4 suggested wake-up times if you fall asleep now • Every card shows the number of sleep cycles and total hours of sleep • More cycle options: 8, 7, 2 and 1 cycles (Pro) • Adjustable fall-asleep buffer, default 15 minutes (Pro) • Recent calculations, reopened in one tap (Pro) • Clean, simple card layout with a 12/24-hour time picker • No accounts, no tracking, no permissions Works offline — nothing is sent anywhere, and recent calculations stay on your device. This is a simple calculator based on the common 90-minute sleep-cycle estimate. It is not medical advice. Remove ads anytime with a one-time in-app purchase. Pro: no ads, unlimited use, all features unlocked. One-time purchase.