Sleep Calculator
Calculate optimal sleep schedules
Sleep Calculator
Plan your bedtime or wake time around 90-minute sleep cycles for fresher mornings.
How It Works
- • A full sleep cycle lasts about 90 minutes; waking at the end of a cycle feels easier.
- • Most adults need 4–6 cycles per night (6–9 hours).
- • We add a ~15 minute buffer for the time it takes to fall asleep.
Privacy & Security
All calculations run locally in your browser. Nothing is stored or transmitted.
Sleep Calculator determines optimal sleep times based on sleep cycles and wake time to improve sleep quality and daytime alertness.
Key Features
Sleep cycle calculation
Wake time optimization
Bedtime recommendations
Sleep stages
REM sleep tracking
Sleep quality analysis
Sleep Calculator
Enter Wake Time
Input when you need to wake up
Calculate Cycles
Determine optimal sleep cycle duration
Get Bedtimes
See recommended bedtimes
Plan Sleep
Adjust schedule for optimal rest
Use Cases
Sleep optimization
Shift scheduling
Jet lag recovery
Health improvement
Frequently Asked Questions
How long is a sleep cycle?
A typical sleep cycle lasts about 90 minutes, consisting of light, deep, and REM sleep stages.
Why should I wake at the end of a sleep cycle?
Waking at the end of a cycle leaves you feeling more refreshed than waking during deep sleep.
How many hours of sleep do I need?
Adults typically need 7-9 hours per night, usually 4-6 complete sleep cycles.
Does this work for shift workers?
Yes, adjust your wake time to your shift schedule and we'll calculate the best bedtime.
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