Hello, and welcome to Caffeine Chart!

I started my caffeine journey in college when I drank dining room coffee to get through studying during finals weeks. I quickly adopted caffeine as a powerful productivity tool. I became interested in calculating how long caffeine stays in the human body to better predict and optimize my energy levels throughout the day. 

Caffeine body levels follow an established trajectory of exponential decay. The average person's half-life is about 5 hours, though this number varies by individual. So, if you know how much caffeine you've consumed and at what times, you can calculate how much caffeine is in your body and how much there will be throughout the day.

I built Caffeine Chart to do these calculations for you. All you need to do is enter your caffeine intakes, and Caffeine Chart will do the math to identify your current and future caffeine levels. We also have other features around bedtime and historical caffeine intakes that I encourage you to try out too.

Please try Caffeine Chart, and let me know what you think!

Sincerely,

Steven

How does it work?

Caffeine body levels follow an established trajectory of exponential decay. The average person's half-life is about 5 hours, though this number varies by individual (source). So, if you know how much caffeine you've consumed and at what times, you can calculate how much caffeine is in your body and how much there will be throughout the day.

How to get started?

1. Add your intakes to view your current and future caffeine body levels.

2. Change your bedtime settings to see how much caffeine you'll have in your body when you go to sleep tonight.

3. See how much caffeine you're consuming day over day in the caffeine calendar.

How much caffeine is in my drink?

Please check your drink's packaging for the caffeine amount. If it's not present, here's a general guide for approximation:

• Drip Coffee (8 oz): 100 mg

• Espresso shot (1 oz): 60 mg

• Black tea (8 oz): 50 mg

These amounts are based on US FDA guidance: https://www.fda.gov/consumers/consumer-updates/spilling-beans-how-much-caffeine-too-much

Caffeine Chart is not a medical app

Caffeine Chart is not a medical app. At its core, it's just a calculator and logbook. Do not treat any information in this app as medical advice.