☕ Caffeine Calculator

How much caffeine have you had today? And when should you stop?

YOUR RESULT
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Total caffeine intake and recommended cutoff time

What this tool helps with

Total caffeine intake and recommended cutoff time

How to get the most out of this tool

Understanding the calculations and biological variation

Human physiology, metabolism, and daily rhythms naturally fluctuate between individuals. The benchmarks applied in this tool evaluate total caffeine intake and recommended cutoff time using widely published health guidelines and empirical averages.

Use these calculations as practical guidelines for daily routine planning, recovery tracking, or fitness goal setting, listening to your body's specific responses.

Best practices for accurate results

  • Enter specific, realistic values: While default approximations give a quick baseline, entering your exact figures produces a substantially more useful result.
  • Test edge cases: Try adjusting one variable at a time (such as increasing or decreasing by 10–20%) to observe which factor creates the greatest impact on the final outcome.
  • Review adjacent tools: Cross-referencing your results with related calculators below helps validate your conclusions and uncover complementary insights.

Frequently Asked Questions

NHS recommends no more than 400mg per day for adults. That's about 4 coffees.
At least 6 hours before bed. Caffeine's half-life is 5-6 hours.