How are speed feats calced?

[The_real_cal_howard]

I am very intrigued by the speed feats. However, how does one tell if someone is going that fast. I understand if it is Beerus, or Seiya, or someone else who has to go (M)FTL+ to travel through space, but for example, how are Naruto or RWBY characters MHS+, or pre Buu Saga characters in the relativistic range or greater (I'm familiar with that recent FTL calc. Tertiary reason why I'm asking this question.) if they are not leaving Earth? If I wanted to create a character who was relativistic, how would I do that? I'm not questioning if they are, I just want to know to be able to do the calculaitons myself.

 

[Peter_"Quicksilver"_Maximoff]

For Basic speed feats, like moving from the earth to outermost atmosphere in a couple of seconds, first you need a distance and time

and caculator like this http://www.calculatoredge.com/civil engg calculator/speed Distance Time.htm