Sleep Calculator

Sleep cycles, alarm & sleep sounds — by smartsleepcalc.com

😴 SLEEP CALCULATOR — Wake Up Refreshed Every Morning Stop guessing when to go to bed. Sleep Calculator uses proven 90-minute sleep cycle science to show you exactly when to sleep or wake up — so you always rise between cycles, not in the middle of one. ───────────────────────────────── 🛌 BEDTIME CALCULATOR Enter when you need to wake up and get 3 ideal bedtime options — Best (6 cycles), Good (5 cycles), and Minimum (4 cycles). Includes the average 14-minute fall-asleep time for accurate results. ⏰ WAKE-UP CALCULATOR Enter when you're going to sleep (or use your current time) and see the best wake-up times based on complete sleep cycles. Wake up naturally feeling rested, not groggy. 🎵 SLEEP SOUNDS (8 ambient sounds) - 🌧️ Rain - 🌊 Ocean Waves - 📻 White Noise - 🌲 Forest - ⛈️ Thunder - 💨 Wind - 🔥 Fireplace - 🏞️ River All sounds are generated directly in your browser — no buffering, no ads, no internet required. ⏱️ SLEEP TIMER Set sounds to automatically fade out after 15, 30, 45, 60, 90, or 120 minutes — or enter a custom duration. Perfect for falling asleep without leaving audio running all night. 🔔 ALARM Set a wake-up alarm with your choice of ambient sound. Includes a 5-minute snooze button. ───────────────────────────────── ✅ WHY SLEEP CALCULATOR? - Based on real sleep cycle science (90-min NREM/REM cycles) - 100% offline — sounds work without internet - No ads, no subscriptions, no account needed - No data collected — ever - Lightweight and fast - Manifest V3 — built to Chrome's latest security standard ───────────────────────────────── 🔒 PRIVACY This extension collects zero data. No tracking, no analytics, no network requests. Everything runs locally in your browser. ───────────────────────────────── Learn more at smartsleepcalc.com