Personally I find that I am unable to do these calculations/estimations unless I write things down. I get lost between powers of 2/MB/TB/nanoseconds and other unit conversions. I understand that this is elementary math, but still, I am just curious, can most people do similar calculations in their head (for instance during a meeting) ?
Powers of 2 are incredibly helpful too: I can estimate that the square root of 4000 is around 60 because 4000 is close to 2 to the 12th, for instance. As a coder it’s well worth your time to memorize powers of 2 up to at least 2 to the 16.
And for 0-9 I have those memorized. So if I'm given the number 2^39 I unwrap that as 512 giga, or just over 500 billion (seems its ~550, but estimating with base 2 is still going to be closer than estimating with base 10)