Caffeine Half-Life Calculator

Track how long caffeine stays in your system. Know when it's safe to sleep without affecting your rest!

Caffeine Consumed

95mg

Moderate

Safe to Sleep

01:05 PM

48mg

After 5.5h (half-life)

21mg

After 12 hours

Caffeine Breakdown Timeline

08:00 AM
95mg
09:00 AM
84mg
10:00 AM
74mg
11:00 AM
65mg
12:00 PM
57mg
01:00 PM
51mg
02:00 PM
45mg
04:00 PM
35mg
06:00 PM
27mg
08:00 PM
21mg

💡 Caffeine Tips

  • • Stop caffeine 6+ hours before bed
  • • Stay under 400mg/day (recommended)
  • • Caffeine peaks 30-60 min after consumption

Features

  • Track caffeine over time
  • Know when to stop for good sleep
  • Multiple drink sources
  • Visual breakdown timeline
  • Custom caffeine amounts

How to Use

  1. 1
    Select a caffeine source or enter custom mg
  2. 2
    Set the time you consumed it
  3. 3
    See how caffeine decreases over time
  4. 4
    Check when caffeine will be low enough for sleep

Frequently Asked Questions

What is caffeine half-life?

The time it takes for half the caffeine to leave your system, typically 5-6 hours.

How much caffeine affects sleep?

Studies suggest keeping under 50mg in your system for quality sleep.