Caffeine Calculator
When should you stop
drinking caffeine?
Track every drink across your day, factor in your actual metabolism, and see exactly how much caffeine will still be working against you at bedtime. The answer is usually later than you think.
01 — Your metabolism
How fast does your body clear caffeine?
The standard '5-hour half-life' applies to less than half of people. Pick the profile that matches you.
02 — Your bedtime
What time do you go to sleep?
Target caffeine under 50mg by 11PM
03 — Your day
Add every caffeinated drink.
Include everything — even the small ones. Dark chocolate, decaf, and tea all contribute. The math adds up faster than you'd expect.
Waiting for your day
Add at least one drink above to see your caffeine curve.
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