What Is Your Chronotype?
Your body has an opinion about what time it is
Being a night owl is not a character flaw and getting up at five is not a virtue. Your internal clock runs on a schedule that is largely biological, partly genetic, and only slightly negotiable. Ten questions will tell you which one you are - and what to do with that information.
Before you start There are no right answers. Pick what is usually true for you, not what sounds best.
Answer as you would on a free week - no alarm, no obligations. That is when your real clock shows itself.
What it measures
Morningness-eveningness: the timing of your body's circadian rhythm, measured through preferred sleep and wake times, when you feel sharpest, and how you cope with being pushed off schedule.
Based on: Circadian chronotype research (Horne & Ostberg morningness-eveningness)
Possible results
Definite morning type
Your best hours happen before most people are awake
Moderate morning type
Early enough to be functional, late enough to have a social life
Moderate evening type
You get good somewhere after lunch and stay good
Definite evening type
The world starts too early and you have always known it
Common questions
Can I change my chronotype?
You can shift it by roughly an hour with consistent light exposure in the morning, darkness in the evening and a stable schedule. You cannot turn a definite evening type into a morning type, and trying hard at it mostly just produces sleep deprivation.
Does chronotype change with age?
Yes, predictably. Children lean early, adolescence pushes the clock dramatically later with a peak around age 20, and it then drifts earlier again for the rest of life. Teenagers are not being difficult about school start times - they are biologically correct.
What is social jet lag?
The gap between the sleep your body wants and the sleep your schedule allows. If you wake at 6:30 on weekdays and 10:00 at weekends, you are effectively flying across three and a half time zones every Friday and back every Monday. It is associated with worse mood, higher body weight and reduced cognitive performance.
Sources
- Horne, J. A., & Ostberg, O. (1976). A self-assessment questionnaire to determine morningness-eveningness in human circadian rhythms. International Journal of Chronobiology.
- Roenneberg, T., Wirz-Justice, A., & Merrow, M. (2003). Life between clocks: daily temporal patterns of human chronotypes. Journal of Biological Rhythms.
- Roenneberg, T., Allebrandt, K. V., Merrow, M., & Vetter, C. (2012). Social jetlag and obesity. Current Biology.
- Patke, A., et al. (2017). Mutation of the human circadian clock gene CRY1 in familial delayed sleep phase disorder. Cell.
An honest note Chronotype is real biology rather than a preference, and it is partly inherited - specific gene variants have been identified in families with extremely delayed sleep timing. But this is a short adaptation of the established questionnaires rather than one of them, and three things limit what a result can tell you. Chronotype moves with age: it drifts later through adolescence, peaks in lateness around twenty, and then shifts steadily earlier for the rest of life, so an answer at seventeen and an answer at fifty are both correct. It is also pushed around by light, by work schedules and by how much sleep you have been getting, which means a stressful few weeks can produce a misleading result. And being an evening type is not a disorder. It becomes a health question only through the mismatch with an early schedule, which is why the practical advice is about morning light and a consistent wake time rather than about becoming someone else. If you cannot sleep or cannot function, that is worth taking to a doctor rather than to a test.