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Caffeine by drink: mg per serving and how long it lasts
Brewed coffee is about 96 mg a cup, espresso 64 mg a shot, black tea 47 mg, cola 33 mg a can. Caffeine's half-life is around 5 hours, so half of any of these is still in you by late evening. Pick a drink for the curve and the last-cup table.
Updated October 3, 2026 · FDA · USDA · Mayo Clinic figures · Drake 2013
| Drink | Serving | Caffeine | Range | Left after 5 h |
|---|---|---|---|---|
| Energy shot | 2 fl oz (60 ml) | 200 mg | 200–200 | 100 mg |
| Cold brew coffee | 12 fl oz (355 ml) | 155 mg | 100–200 | 78 mg |
| Brewed coffee | 8 fl oz (237 ml) | 96 mg | 80–100 | 48 mg |
| Energy drink | 8 fl oz (237 ml) | 72 mg | 40–250 | 36 mg |
| Matcha (1 tsp powder) | 8 fl oz (237 ml) | 70 mg | 38–88 | 35 mg |
| Espresso | 1 fl oz (30 ml) shot | 64 mg | 47–75 | 32 mg |
| Instant coffee | 8 fl oz (237 ml) | 62 mg | 27–173 | 31 mg |
| Black tea | 8 fl oz (237 ml) | 47 mg | 25–48 | 24 mg |
| Cola | 12 fl oz (355 ml) can | 33 mg | 30–40 | 17 mg |
| Green tea | 8 fl oz (237 ml) | 28 mg | 25–29 | 14 mg |
| Dark chocolate | 1 oz (28 g) | 24 mg | 12–30 | 12 mg |
| Decaf coffee | 8 fl oz (237 ml) | 2 mg | 2–15 | 1 mg |
Typical values; brands vary · FDA, USDA FoodData Central, Mayo Clinic · as of October 3, 2026
Half-life 5 h (IOM 2001); shaded band = FDA 4–6 h
When should the last cup be?
The one controlled trial on timing found that 400 mg six hours before bed still cut sleep by more than an hour. Cutoff times by bedtime → or use the last-coffee calculator.
Sources
- Caffeine content for coffee, tea, soda and more — Mayo Clinic
- Spilling the Beans: How Much Caffeine is Too Much? — U.S. Food and Drug Administration
- FoodData Central — U.S. Department of Agriculture
- Caffeine Effects on Sleep Taken 0, 3, or 6 Hours before Going to Bed — J Clin Sleep Med 9(11):1195-1200, 2013 (Drake C. et al.)
- Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations — National Academies Press, 2001
General information from population studies (NIH, CDC, NSF, AASM). It is not medical advice and does not replace a clinician who knows you.