Caffeine Intake Calculator
Track daily caffeine intake from coffee, tea, energy drinks, and soda.
Returns total mg and shows if you are within the FDA safe limit of 400 mg per day.
Caffeine is a naturally occurring stimulant found in coffee beans, tea leaves, cacao, guarana berries, and many other plants. It is the world’s most widely consumed psychoactive substance, and when consumed within recommended limits, is safe for most healthy adults.
FDA recommended maximum: 400 mg per day for healthy, non-pregnant adults, roughly equivalent to 4 standard cups of coffee.
Caffeine content by source (approximate per serving):
| Source | Serving Size | Caffeine |
|---|---|---|
| Brewed coffee (drip) | 8 oz / 240 mL | 80–135 mg |
| Espresso shot | 1 oz / 30 mL | 60–75 mg |
| Double espresso (doppio) | 2 oz / 60 mL | 120–150 mg |
| Cappuccino / latte | 12 oz / 355 mL | 60–80 mg |
| Cold brew coffee | 8 oz / 240 mL | 100–200 mg |
| Black tea (brewed) | 8 oz / 240 mL | 40–70 mg |
| Green tea | 8 oz / 240 mL | 25–45 mg |
| White tea | 8 oz / 240 mL | 15–30 mg |
| Matcha | 8 oz / 240 mL | 60–80 mg |
| Energy drink (Red Bull) | 8.4 oz / 250 mL | 80 mg |
| Energy drink (Monster) | 16 oz / 473 mL | 160 mg |
| Cola (Coca-Cola) | 12 oz / 355 mL | 34 mg |
| Dark chocolate | 1 oz / 28 g | 12–20 mg |
| Milk chocolate | 1 oz / 28 g | 3–6 mg |
| Pre-workout supplement | 1 scoop | 150–300 mg |
Population-specific guidelines:
| Population | Recommended Limit |
|---|---|
| Healthy adults | ≤ 400 mg/day |
| Pregnant women | ≤ 200 mg/day (WHO/ACOG) |
| Breastfeeding women | ≤ 200–300 mg/day |
| Adolescents (13–18) | ≤ 100 mg/day (Health Canada) |
| Children (under 12) | Not recommended |
| Those with anxiety, arrhythmia, or hypertension | Reduced or none — consult a doctor |
Caffeine half-life: Caffeine’s half-life in the body is approximately 5–6 hours for most adults. This means if you consume 200 mg at noon, about 100 mg is still in your system at 5–6 PM, and 50 mg remains at 10–11 PM.
Worked example: Morning routine: 2 cups of drip coffee (2 × 100 mg = 200 mg) Midday: 1 can of cola (34 mg) Afternoon: 1 matcha latte (70 mg) Total = 304 mg — within the recommended limit.
Signs of excessive caffeine intake:
- Jitteriness, anxiety, or rapid heartbeat
- Difficulty sleeping (even when consumed in the afternoon)
- Headache (paradoxically: both too much and withdrawal can cause headaches)
- Gastrointestinal discomfort
- Frequent urination