Free caffeine and sleep calculator
Plan your caffeine around tonight's sleep
Add the coffee, tea, energy drinks, or supplements you use in a day. See what may still be active at bedtime, then find a caffeine pattern that supports your energy without quietly working against your sleep.
Interactive model
Plan your caffeine around bedtime
See what may still be active at bedtime, then adjust the timing or amount of each intake.
Peak level
117 mg
At bedtime
23 mg
Sleep reference
Within your reference
Common patterns
Daily anchors
Used to frame the chartCaffeine intakes
Add each drink, supplement, or other source.
Common caffeine amounts
Typical estimates, not exact product values.
Single-serve coffee
About 100 mg
Double espresso
About 120 mg
Can of cola
About 34 mg
Energy drink
About 80 mg
This visualization estimates caffeine remaining from reported intake and a chosen half-life. Optional sleep-pressure lines are physiology- informed visual proxies, not direct measurements of adenosine or what your brain feels. Use this as a planning reference rather than an exact scientific or medical assessment.
Make a clearer call
Use the estimate to make caffeine fit your actual day
A fixed rule like “no coffee after 2 p.m.” cannot account for an earlier bedtime, a larger drink, or the way your body clears caffeine. This gives you a practical starting point to test against the sleep you want to protect.
Choose a cutoff that fits bedtime
Work backward from the time you want to sleep instead of using a one-size-fits-all clock time.
See the whole day, not just one drink
A morning coffee, lunch soda, and late pre-workout can add up differently than any one of them does alone.
Find a pattern worth trying
Use the result as a planning estimate, then pay attention to how easily you fall asleep and how restored you feel.
An estimate, not a verdict
Caffeine metabolism varies with the person, dose, medications, and other factors. The calculator cannot predict a night of sleep exactly. It can help you notice whether a late drink is worth moving earlier, reducing, or leaving out for a while.