Well most physicists assume it is massively bigger than we can see. It is in principle possible that we see nearly all of it, but that would be very coincidental. The only thing we know is that it is at least as big as we can observe, but it could be hundreds of times bigger, 10^100, or even infinite.

There are speculations one could make that imply a minimum size, I recall a reading a prediction of 10^50 times bigger or so.