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.
Best Travel CPAP Machines (2026): AirMini vs. Transcend Micro vs. Z2 Auto
The best travel CPAP machine for most people is still the ResMed AirMini — if you can tolerate its waterless humidification and proprietary tubing.
The Air Has to Get In: CPAP Masks and Fitting, Followed From Blower to Throat
The number most Canadians meet first is four. Four hours a night, on seventy percent of nights. That's the adherence threshold American insurers set decades ago, and Canadian clinics inherited it the…
Samsung product strategy now runs through your bedroom
The most upvoted question in Samsung's Reddit AMA wasn't about hinge durability or the crease. It was a complaint, phrased politely and voted to the top by people who clearly meant it: take some risks…
“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