Your circadian rhythm (body clock), explained
You run on an internal 24-hour clock. When your day fits it, everything is easier. When it does not, you feel it.
The 24-hour clock inside you
Your circadian rhythm is a roughly 24-hour cycle set by a master clock in the brain and synced mainly by light. It drives when you feel sleepy and alert, your body temperature, hormone timing and more.
Morning light anchors the clock and sets the timer for melatonin roughly 14 to 16 hours later. Bright light late at night pushes the whole rhythm later, which is why screens before bed shift your sleep.
Chronotype: early bird or night owl
Where your clock naturally sits is your chronotype. Some people are genuinely wired earlier, some later, and it is largely biological, not a matter of discipline. Fighting your chronotype every day is a quiet, constant cost.
Alignment is how closely your actual sleep and wake times match your natural rhythm. The bigger the gap, the more it shows up as poor sleep, low morning energy and a harder afternoon.
How TIDES reads it
TIDES reads your rhythm from your real timing and shows it on a 24-hour dial you can drag, with your chronotype and a 0 to 100 alignment read. It recommends tonight's window against your habitual rhythm, and it is honest that this is a behavioural alignment estimate, not a biological phase measurement.
Common questions
What is a circadian rhythm?
It is your internal, roughly 24-hour clock, set by a master clock in the brain and synced mainly by light. It drives your sleep timing, energy, alertness, body temperature and hormone timing.
What is a chronotype?
Your chronotype is where your body clock naturally sits, earlier (morning type) or later (evening type). It is largely biological, and consistently fighting it carries a cost to sleep and energy.
How do I fix my circadian rhythm?
Get bright light early, limit bright light late, and keep consistent sleep and wake times close to your natural rhythm. Aligning your day to your clock, rather than forcing the clock, is what works.