Sleep Calculator
Calculate the best time to sleep or wake up based on 90-minute sleep cycles.
Sleep Calculator
How It Works
1
Select Time
Choose your wake-up time or bedtime
2
Choose Cycles
Select how many sleep cycles you want
3
Calculate
Get your optimal sleep schedule
FAQs
What is a sleep cycle?
A sleep cycle is about 90 minutes and includes all sleep stages.
How many cycles do I need?
Most adults need 5-6 cycles (7.5-9 hours) for optimal rest.
Why 90 minutes?
Research shows the average sleep cycle is 90 minutes long.
Is this accurate?
This is based on sleep science but individual needs may vary.
Is it free?
Yes, this calculator is completely free to use.