Min/Max values for X, Y, Z coordinates?

What are the minimum and maximum allowed values for x, y, and Z coordinates in OpenGl? I’m contemplating a BIG simulation and am wondering whether I’ll have to rescale as users go from one level to another, or if it’ll all fit in the same coordinate system.

The default min/max of viewport and window are (-1, +1), (-1 , +1) and (-1, +1) for x,y,z-axis respectively. However the sacling factor depends on aspect ratio of windows to viewport.

AFAIK most GL implementations use single precision floats internally. this would limit the value range to +/- 3.4*10^38

can you give more information about what you intend to visualize and how?