Dunkin' Brewed Coffee (Medium) Caffeine Half-Life & Bedtime Decay
A standard Medium hot drip coffee from Dunkin' contains 210mg of caffeine, slightly higher than a Celsius energy drink.
Interactive Stack Calculator for Dunkin' Brewed Coffee (Medium)
We've preloaded Dunkin' Brewed Coffee (Medium) (210mg) below. Adjust your planned bedtime or add other drinks to see your exact curve.
Caffeine Half-Life & Cutoff Calculator
Caffeine's half-life ranges from about 4 to 7 hours depending on how fast you metabolise it. Add what you've already drunk today to find the last time your next drink still leaves under 50 mg in your system at bedtime.
Caffeine Sensitivity
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Last safe 210 mg drink
For this drink size, the safe window closed earlier today. A smaller drink, or decaf, may still fit.
Today's drinks alone leave about 32 mg at bedtime.
Solid: caffeine from today's drinks.
Stop guessing your cutoff.
Here you type your drinks in. ARC does the same math from every drink you log in one tap, moves your last safe coffee the moment you log a cup, shows it as a live countdown, and tells you plainly when no cup fits any more.
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Dunkin' Brewed Coffee (Medium) Hour-by-Hour Caffeine Decay Table
Pharmacokinetic Decay (5.5h Half-Life)Exact milligrams of caffeine remaining in the bloodstream at 2-hour intervals if consumed at various times of day, based on an average human caffeine half-life of 5.5 hours. Target is less than 50mg active at 11:00 PM bedtime.
| Intake Time | +2 hrs | +4 hrs | +6 hrs | +8 hrs | +10 hrs | +12 hrs | At 11 PM Bed | Status |
|---|---|---|---|---|---|---|---|---|
| 08:00 AM | 163 mg | 127 mg | 99 mg | 77 mg | 60 mg | 46 mg | 32 mg | ✓ Sleep Safe |
| 12:00 PM (Noon) | 163 mg | 127 mg | 99 mg | 77 mg | 60 mg | 46 mg | 53 mg | ✕ Above 50mg |
| 02:00 PM | 163 mg | 127 mg | 99 mg | 77 mg | 60 mg | 46 mg | 68 mg | ✕ Above 50mg |
| 04:00 PM | 163 mg | 127 mg | 99 mg | 77 mg | 60 mg | 46 mg | 87 mg | ✕ Above 50mg |
Cutoff Recommendation: Cut off by 1:30 PM for an 11:00 PM sleep target.
Values are calculated using the standard exponential decay model: mg_remaining = initial_mg * 0.5^(hours / half_life).
How Your Genetics (CYP1A2) Impact Dunkin' Brewed Coffee (Medium) Clearance
Over 95% of caffeine metabolism takes place in your liver via the cytochrome P450 enzyme CYP1A2. Depending on whether you carry the fast or slow metabolizing gene variant, clearance times for 210mg vary drastically:
Residual after 8 hours: 53 mg. You clear caffeine rapidly and rarely experience insomnia from lunch beverages.
Residual after 8 hours: 77 mg. Standard biological decay rate representing ~50% of the population.
Residual after 8 hours: 95 mg. CYP1A2*1F carriers. Any caffeine consumed past noon will disrupt sleep architecture.
Frequently asked questions
How many hours does Dunkin' hot coffee take to clear?
With 210mg, it takes approximately 11.5 hours to clear down to 50mg in an average human body.