Does caffeine leave the body at one exact time?
No. This tool shows a mathematical estimate based on the half-life you select. Caffeine metabolism varies between people and circumstances.
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Sleep and Caffeine Planner
Plan an asleep-by time and estimate how much caffeine may remain from each drink using an adjustable half-life model.
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Your overnight plan
Wind down at 10:30 PM
Aim to be asleep by 11:00 PM for 8 hours before a 7:00 AM wake-up.
37 mgAt asleep-by time
12 mgAt wake time
Modeled caffeine remaining
11:00 PM37 mg
7:00 AM12 mg
Drink-by-drink estimate
09:00 · 95 mg14 mg at bedtime
14:00 · 80 mg23 mg at bedtime
What the result means
A schedule and a decay model, not a sleep diagnosis
The planner counts backward from your chosen wake time to create an asleep-by target. It then applies exponential decay to each caffeine entry using the half-life you selected.
Caffeine metabolism and sleep needs vary. The remaining milligrams are an estimate for comparing timing scenarios, not a promise about when caffeine is gone or how well you will sleep.
remaining caffeine = amount x 0.5(hours elapsed / half-life)
Common questions
Does this planner predict sleep quality?
No. It compares a sleep schedule with a caffeine decay estimate. It cannot predict whether you will fall asleep or how restorative your sleep will be.
Is my information uploaded?
No. The calculation runs inside your browser. Kiomora does not receive the wake time, sleep target, or caffeine entries you add here.
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