The Caffeine Clearance Calculator · About 60 seconds
The Afternoon Caffeine Fade Calculator
How much of your coffee might linger at bedtime? Choose a drink and explore an estimated caffeine fade, plus a timing target for next time.
Free. No email required. This estimates one serving, not your total daily caffeine.
Your single-serving estimate
Estimated caffeine at bedtime
Bands: low ≤15 mg · middle >15 to <50 mg · high ≥50 mg. These are this tool’s planning bands, not validated sleep-risk thresholds. Classification uses the unrounded estimate.
Your timing target
The target is at most 15 mg from this serving by bedtime—not a safe-sleep guarantee or complete clearance. This decay model approaches zero without reaching it for a positive dose. Other drinks add to the amount remaining.