Daylight Savings Sleep Impact Calculator
See how daylight savings affects your sleep and get a prep schedule. Enter your sleep times and direction to get a personalised adjustment plan.
--
days to fully adjust
--
sleep change first night
4-day prep schedule
Light exposure timing
Common questions
Why does losing 1 hour of sleep matter so much?
Even one hour of sleep loss disrupts your circadian rhythm. Studies show a 24% increase in heart attacks the Monday after spring forward, plus measurable drops in concentration and reaction time that last several days.
What are the health effects of daylight savings?
Research links DST transitions to increased heart attacks, car accidents, workplace injuries, and mood disturbances. Spring forward is worse because you lose sleep. Fall back is easier but can still disrupt routine for 1-2 days.
How can I prepare for daylight savings?
Shift your bedtime 15 minutes earlier (spring) or later (fall) each night for 4 days before the change. Get bright light exposure in the morning after spring forward. Avoid caffeine after noon during the transition week.
Which countries don't observe daylight savings?
Most of Asia, Africa, and South America do not observe DST. Notable countries include Japan, China, India, and Russia. Arizona and Hawaii in the US also skip it. The EU has voted to abolish DST but implementation has been delayed.