Wake-Up Time Calculator
When to set your alarm if you go to bed now.
Your result
Adults generally need 7–9 hours, which means 5–6 full cycles.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Learn more
Sleep Hygiene: Ten Habits for Better Nights
Small changes to routine and environment improve sleep quality.
Sleep & Mental WellbeingSleep Cycles and How to Wake Up Refreshed
Why timing your alarm around 90-minute cycles can help.
Sleep & Mental WellbeingHow Much Sleep Do Adults Need?
Seven to nine hours for most adults, and the cost of shortchanging it.
Frequently asked questions
What does the Wake-Up Time Calculator do?
When to set your alarm if you go to bed now. Enter your values and the result and chart update instantly.
How accurate is it?
It uses published, widely used formulas. Results are estimates for education and planning, not a diagnosis. Talk to a qualified clinician about decisions affecting your health.
Is my information stored or shared?
No. All calculations run in your browser and nothing you type is sent to a server or saved.
What can I search to find this tool?
People find it by searching for: what time to wake up; alarm for a nap or night sleep; going to bed now.