Definition
- Chronotype
- Chronotype is an individual’s natural preference for when to sleep and be active. It is largely genetic, shifts with age, and is commonly described on a spectrum from early types who wake naturally at dawn to late types who are most alert in the evening.
It is a spectrum, not four boxes
Popular systems dividing people into named animal types are a simplification. Research treats chronotype as continuous, usually measured by the midpoint of sleep on free days. Most people sit somewhere in the middle rather than at either extreme.
Why it matters
A late chronotype forced onto an early schedule accumulates sleep debt during the week and compensates at weekends, producing social jetlag. Knowing your chronotype does not let you ignore your obligations, but it does tell you how much of a shift you are attempting and therefore how gradual it needs to be.