e: Spacetime Converter

Have you thought about how old you are - in meters?
Or how tall you are - in seconds?
Or how many miles it is until your next birthday?
Let's think out of the box, relativistically. While spacetime intervals are constant, length and time can be converted to each other. This calculator makes use of geometrized units (where the speed of light is unity) and lets you convert conveniently between length and time.
Is this a useful conversion tool in your day-to-day life? Probably not. But maybe it will let you think about the world a little differently. And amuse your friends and family at the same time!
For a technical reference, refer to "Gravitation", by Misner, Thorne and Wheeler, 1973, W.H. Freeman and Company, pp. 35-36.
To make things more accessible to the average user, we have tried to avoid displaying scientific notation in numbers as much as possible and, instead, make use of more common terms, such as "billions of miles" and "milliseconds".
Now upgraded with the ability to choose different lengths and times for input (inches, hours, days, etc.)!
keywords: science, physics, space, time, relativity, calculator
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Reviews from around the world:
from Fox Knight, US
Love this app!!
from highschool student, US
Good job, there's a lot of potential here. . .
from Turbo elf, US
Science geek must buy
from Letter Warrior, US
I love this idea, especially seeing how far it is until tomorrow, or a friend's birthday.
from Professor and wife, US
A great application that can also be used by students ... really is a wonderful game.