Social jet lag is what happens when your schedule pulls sleep timing sideways.
Social jet lag is a gap between workday and free-day sleep midpoint. It is timing context, not a medical label.
What is social jet lag?
Social jet lag is commonly estimated by comparing the midpoint of sleep on workdays with the midpoint of sleep on free days.
The simple definition
Social jet lag describes a mismatch between the sleep timing your body tends toward and the timing your social or work schedule forces.
The common calculation uses the difference between sleep midpoint on workdays and free days.
A useful reading
daygauge does not tell you that you have a disorder. It shows your sleep timing against your usual window, so a weekend that started 92 minutes later than usual is easy to spot.
A reading like that is easier to act on than a vague sense of being tired or inconsistent.
What to experiment with
A reasonable experiment might be a smaller weekend wake-time shift, earlier outdoor light, or a gentler Sunday evening routine.
A Quest such as holding a consistent sleep window tests this against your next comparable readings. Check whether the gap narrows and whether your sleep, movement and readiness change against your own average.
The useful question is not “do I have social jet lag?”
A more useful question is: when your free-day midpoint moves later, what else moves with it? daygauge can put next-day movement, time in daylight, mood ratings and readiness beside your own average.
Weekend sleep started 96 minutes later than usual. Monday movement was lower than your average and the late timing carried into two nights. Try a smaller Sunday wake-time shift and check whether your timing settles next week.
A pattern like that gives you something to test, not a judgement about your lifestyle.
Further reading.
These studies describe groups of people. They help explain the topic, but they cannot tell you what will happen to you.
- Social jetlag: misalignment of biological and social time
- Social Jetlag and Related Risks for Human Health: A Timely Review
- Chronotype and social jetlag critical review
Research context only. daygauge does not diagnose, treat, prevent or predict disease risk. Personal medical concerns belong with a qualified clinician.
Related guides.
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