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Caffeine Half-Life Tracker

How much caffeine is still in your body.

Caffeine in your system right now
0 mg
In 4 hours
0 mg
In 8 hours
0 mg

Add a drink

About

Caffeine has a half-life of about 5 hours. Enter what you've had today (coffee, tea, soda, energy drinks, supplements) and the tool plots how much is still active in your body. Helps you avoid caffeine too late in the day, which wrecks sleep.

How to use

  1. Add drinks with the time you had them.
  2. Read the current and projected caffeine levels.

FAQ

Is the 5-hour half-life accurate for everyone?+

Roughly. Genetics affect caffeine metabolism by 2-4×. Some people clear it in 3 hours, others take 8+. The tool uses 5 hours as an average.