Chronotype Calculator
Are you a morning lark or night owl? Uses mid-sleep time.
Your result
Chronotype is based on the middle of your sleep on free days, corrected for sleep debt. A big gap between work-day and free-day sleep is called social jet lag.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Learn more
Chronotypes: Are You a Lark or an Owl?
Your internal clock influences when you feel best.
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 Chronotype Calculator do?
Are you a morning lark or night owl? Uses mid-sleep time. 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: am i a night owl; morning person or evening person; best time to work out; natural sleep schedule.