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Caffeine Calculator
Free caffeine calculator: add coffee, tea, cola, energy drinks and chocolate to see your daily caffeine against the 400 mg a day the FDA says healthy adults can usually have, and how much is left at bedtime.
Caffeine calculator
Add up your caffeine for the day and see how much is still in your body at bedtime.
Caffeine today
If all of it were drunk at once, about 63 mg would still be in your body at bedtime (half-life about 5 hours; it varies from about 2 to 10).
✅ Rules last checked:
📚 Official sources: FDA: Spilling the beans: how much caffeine is too much?
We build every tool from the official rules and re-check them when they change. Always confirm with the official source before you rely on a result.
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Questions people ask
How much caffeine is too much?+
The FDA says up to 400 mg a day is not generally linked with harmful effects for healthy adults. People who are pregnant, sensitive or taking certain medicines may need less.
Why does coffee keep me awake?+
Caffeine has a half-life of about 5 hours: half of it is still in your body 5 hours later. Many people sleep better with no caffeine after early afternoon.