Caffeine Curve
How much caffeine is in you right now, and how much will be left at bedtime. Add doses, drag them around, or switch to any other substance with a half-life.
The model
One compartment, with first-order absorption and first-order elimination. Each dose is absorbed with a half-time of about ten minutes and then cleared with a half-life of five hours by default, and the doses add up. It's a sketch for curiosity. It is not medical advice, and half-lives vary a lot between people.
Your doses are saved in your browser and go nowhere else.