Coffee you love.
Sleep you need.
Most advice treats them as enemies. We think they've just been badly introduced. JavaSleep is a slow magazine about the hours between your last sip and your first dream — with honest reviews, quiet science, and one very useful calculator.
How much caffeine
will still be awake
at your bedtime?
Caffeine doesn't clock out when you do. It has a half-life of about five hours, which means your 3 PM latte is still at half strength when you're trying to fall asleep at 11. Here's the honest math.
Adjust the inputs above to see your personal timeline.
Three things worth reading slowly.
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Smartwatch Reviews Skip the Dinner Jacket: Four Watches, Eight Weeks, One French Cuff
Most smartwatch reviews are written in daylight, on a treadmill, by someone in a hoodie. Mine started in a hotel bathroom at 11:15pm, in a rented dinner jacket, trying to work out whether the thing on…
Sleep Apnea Travel Logistics: Three Ways to Get Treated Air Away From Home
The number everyone quotes is 8,000 feet. That's the maximum cabin altitude the FAA permits inside a pressurized airliner — the thin-air equivalent your lungs are working against somewhere over…
“The most civilized thing a person can do is enjoy a cup of coffee at ten in the morning and still sleep at ten at night.— Editor's Note, Issue №001