Sleep Calculator - SleepCal

Wake up refreshed, not exhausted. Based on the 90-minute sleep cycle science—calculate your perfect bedtime in seconds. Try it free tonight!

Tired of waking up exhausted?

It's not about sleeping longer—it's about waking up at the RIGHT time.

Your brain cycles through 90-minute sleep stages. Wake up mid-cycle, and you'll feel groggy. Wake at the end of a cycle, and you'll feel refreshed. SleepCal calculates the perfect time for you.

HOW IT WORKS 【WAKE UP MODE】 Tell us when you need to wake up. We'll show you the 3 best times to fall asleep—each aligned with a complete sleep cycle.

【SLEEP NOW MODE】 Going to bed now? We'll calculate the ideal wake times so you rise naturally refreshed.

【POWER NAP】 Need a quick recharge? Our smart nap timer helps you rest without oversleeping or ruining your night.

FEATURES • Sleep Cycle Calculator based on 90-minute science • 40+ nature sounds & white noise for faster sleep • Custom alarm sounds—import your own music (Pro) • Reliable wake-up with Time-Sensitive Notifications • Apple Watch support for silent alarms • Minimalist dark UI—easy on your eyes at night • Privacy-first: all data stays on your device

WHY SLEEEPCAL? We don't track your sleep. We don't need sensors. Just pure, science-based calculation to help you wake up feeling human again.

Download now. Wake up better tomorrow.

ABOUT SUBSCRIPTIONS SleepCal Premium unlocks custom alarms, exclusive sounds, and cloud sync. • Monthly: $4.99/month • Yearly: $19.99/year (Save 67%)

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