Why 7.5 hours often beats 8
Sleep happens in roughly 90-minute cycles. Wake up at the end of one and you'll feel fresh — wake up mid-cycle and even an extra hour can leave you groggy.
Calculate yours →Sleep Blog
Sleep, decoded.
Short, evidence-based articles to help you fall asleep faster, wake up sharper, and stop guessing about bedtime.
The 2 PM caffeine cutoff
Caffeine has a half-life of 5–6 hours. A 3 PM coffee still has 50 mg of caffeine in your system at 9 PM — enough to delay sleep onset by 30+ minutes.
Test it tonight →Beating jet lag with light
Your circadian rhythm follows light, not the clock. 10 minutes of bright morning sun in your destination resets it faster than melatonin alone.
Plan your bedtime →Shift work without wrecking sleep
If you can't change when you sleep, control how you sleep: blackout curtains, cool room (65–68°F), and a ritual your body recognizes as "night."
Get a schedule →Sleeping well with young kids
You may not get long sleep, but you can get good sleep. Protect the first 3 hours — that's when most deep sleep happens, and it does the heaviest lifting.
Find your bedtime →The 4-7-8 breath, in real life
Inhale 4 seconds, hold 7, exhale 8. It activates your parasympathetic nervous system — the same one that takes over during sleep. Three cycles is usually enough.
Pair it with a bedtime →Stop guessing. Start sleeping smarter.
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