It's 3:00 PM on a Monday. Your client, who lives three time zones away, just gave you a critical assignment with a strict 48-hour deadline . You quickly do the mental math: 3:00 PM on Tuesday is 24 hours... so 3:00 PM on Wednesday is 48 hours. Easy, right? But what if the time was 3:47 PM? Or what if the deadline was for 53 hours instead of a neat 48? The moment you have to cross midnight, count minutes, or calculate past a full 24-hour cycle, the mental gymnastics begin. And when your income depends on hitting that precise moment, "close enough" is simply not good enough. The Pain of Manual Time Calculation For anyone working remotely, managing projects, or dealing with international shipping and logistics, constantly calculating future dates and times is a low-key form of stress. Here are scenarios where the manual approach fails you: The Global Client: You get an urgent message: "We need this by 65 hours from now." Your brain freezes trying to figure out ...