Caffeine Calculator
Calculate total daily caffeine intake from multiple sources and assess safety level based on FDA guidelines.
Formula
Total mg = Σ (servings × mg per serving); FDA limit = 400 mg/day for healthy adults
- Coffee: ~95 mg per 8 oz. Espresso: ~63 mg per shot.
- Energy drink: ~80 mg per 8 oz. Black tea: ~47 mg. Cola: ~34 mg per 12 oz.
- FDA safe limit: 400 mg/day for healthy adults. Pregnant: 200 mg/day.
2 coffees + 1 tea
Inputs
- Coffee (8 oz cups): 2
- Espresso shots: 0
- Energy drinks (8 oz): 0
- Tea (8 oz cups): 1
- Cola soda (12 oz cans): 0
- Body Weight: 150 lbs
2×95 + 47 = 237 mg. 59% of 400 mg FDA limit. Moderate — within safe range.
Frequently asked questions
How much caffeine is too much?
The FDA recommends no more than 400 mg/day for healthy adults. That is about 4 cups of coffee.
What are signs of too much caffeine?
Jitteriness, anxiety, heart palpitations, insomnia, headache, and digestive issues.
How long does caffeine stay in your system?
The half-life of caffeine is about 5–6 hours. 400 mg at noon means 200 mg still active at 6 PM.
Is caffeine safe during pregnancy?
Most guidelines recommend keeping caffeine under 200 mg/day during pregnancy. Consult your OB.