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This Caffeine Calculator Helps You Plan Your Day


Caffeine can make you more alert, but so can a good night’s sleep. Until now, if you wanted to plan out your caffeine consumption in detail, the tool to use was 2B-alert, which is fantastic but clunky and hard to read. But now, omnicalculator has made a simplified version they call the Coffee Kick Calculator.

To use it, you just tell the calculator when you woke up and how much sleep you got. Then enter the times and types of your caffeinated beverages. Here’s how your alertness looks throughout the day (the higher the line, the more alert you are) if you had a full eight hours and woke up at 6 a.m.:

The way this calculator measures “alertness,” you have 100 percent when you wake up, dipping to 81 percent around 11am, rising up a little around 8pm, and falling off rapidly after 11. Sounds good. So what if we have a large brewed coffee right when we wake up?

Excellent, we’ll be extra-alert in the morning and we still get tired around the same time at night. But what if we’re really feeling that after-lunch slump and have a large coffee (which I’m entering as 1.5 cups) then as well?

The coffee will do its job, and throughout the work day we’ll be a lot more alert than if we hadn’t had any at all. But the graph looks like a roller coaster, an alert pops up saying that we’ve had more than 400 milligrams today (we’ll live, but it’s not ideal), and we’re a little more alert at bedtime.

In reality, nobody is as perfect as a calculator: some of us get more of a boost from caffeine than others, and the more often you drink it, the less it helps.

If you want to really nerd out about your caffeine consumption, the original 2B-alert can model multiple days of sleep deprivation, and compare different caffeine schedules against one another. But for an everyday understanding of what happens when you get a boost of caffeine, Coffee Kick will do the job.