Is 400 mg safe for everyone?
400 mg is FDA guideline for healthy adults. Pregnant women: 200mg. People with anxiety/heart conditions should consume less.
Health Fitness
Caffeine Intake Calculator
Calculate caffeine intake with your details.
Personalized estimate
Use realistic inputs for the most useful results.
What this calculator does
A caffeine intake calculator tracks daily consumption from all sources. FDA recommends max 400 mg daily for healthy adults—about 4 cups of coffee.
How it works
Multiply servings by caffeine content per serving. Standard: coffee 95mg, espresso 63mg, tea 40mg, energy drinks 160mg.
Formula
Total caffeine = Σ(caffeine per serving × servings). Percent of limit = (total ÷ 400) × 100.
Tips for using this calculator
- Avoid caffeine after 2 PM—5-6 hour half-life affects sleep
- Pregnant women should limit to 200 mg
- Stay hydrated as caffeine is mildly diuretic
- Gradually reduce to avoid withdrawal headaches
- Green tea offers caffeine with calming L-theanine
Frequently asked questions
Why does caffeine affect sleep?
5-6 hour half-life means 50mg remains active at bedtime from afternoon coffee.
Which has more caffeine: energy drinks or coffee?
Energy drinks (160mg) have slightly more than one coffee (95mg), but large coffees can exceed 200mg.