Soluna Sleep

Know when to sleep. Wake up restored.

Your body runs on 90-minute sleep cycles. Wake at the wrong moment and you feel groggy — wake at the right one and you feel human.
Our free calculators help you find that moment.

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Free Sleep Calculators

Find Your Perfect Sleep Schedule

Science-backed tools for better rest, based on 90-minute sleep cycle research.

Sleep Cycle Calculator

Enter your bedtime and get the ideal wake-up times based on 90-minute sleep cycles.

Calculate wake times →

Wake-Up Time Calculator

Need to wake at a specific time? Find the best bedtimes to fall asleep tonight.

Find my bedtime →

Best Bedtime Calculator

Enter your age and lifestyle for a personalized optimal bedtime window recommendation.

Get my bedtime →

Circadian Rhythm Guide

An elegant visual wheel showing peak energy, rest, digestion, and focus windows throughout the day.

View the guide →
Common Questions

Sleep Science FAQ

What is a 90-minute sleep cycle?
Sleep occurs in repeating cycles of roughly 90 minutes, each containing light sleep (N1/N2), deep sleep (N3), and REM sleep. Waking at the end of a complete cycle — rather than mid-cycle — leaves you feeling alert and refreshed instead of groggy.
How many sleep cycles do I need?
Most adults feel best with 5 complete cycles (7.5 hours). Four cycles (6 hours) is a minimum for most people, and six cycles (9 hours) is ideal during recovery, illness, or intense training periods.
Why does Soluna add a 14-minute buffer?
Research shows the average adult takes about 10–20 minutes to fall asleep after lights out. Our calculators use a 14-minute average so your wake time recommendations account for this natural sleep-onset latency.
What is circadian rhythm and why does it matter?
Your circadian rhythm is a roughly 24-hour internal clock governed by light, temperature, and social cues. It regulates when you feel sleepy or alert, and misaligning sleep with your rhythm leads to poor sleep quality even if the duration is adequate.
Is this medical advice?
No. Soluna Sleep provides general wellness information based on published sleep science. If you have a sleep disorder, persistent insomnia, or other health concerns, please consult a qualified healthcare provider.