2^128 ~= 3.4 x 10^38 [0] Age of the universe in seconds ~= 4.3 x 10^17 [1] So assuming you're using an unsigned int to represent the number of seconds from th

2^128 ~= 3.4 x 10^38 [0] Age of the universe in seconds ~= 4.3 x 10^17 [1] So assuming you're using an unsigned int to represent the number of seconds from the big bang, you'll still have ~ 10^21 seconds left on the clock (31.7 trillion years). Unless you're working with a timeline that extends out to the heat death of the universe (10^100 -> 10^(10^56) years), 128 bits should be enough. [0] https://www.wolframalpha.com/input/?i=2%5E128 https://www.wolframalpha.com/input/?i=2%5E128 [1] https://www.wolframalpha.com/input/?i=age+of+the+universe+in+seconds https://www.wolframalpha.com/input/?i=age+of+the+universe+in...