How Long Does Caffeine Stimulate You? Understanding the Factors
                                
                                
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                                    4 min read                                
                            
                                According to the Sleep Foundation, the half-life of caffeine can range from 2 to 12 hours, a surprisingly wide variation that depends heavily on the individual. This means while one person may feel alert for just a few hours after their morning coffee, another can be stimulated by that same cup well into the evening.