According to Microsoft, the page file sizes of 64-bit and 32-bit Windows are 256TB and 16TB respectively.
In 64-bit, the virtual address looks like this:
With 4 levels of 9-bit memory mapping fields and 12-bit offset within page, 64-bit Windows can map maximum 29+9+9+9+12 byte = 256TB.
In 32-bit, the virtual address looks like this:
With 2 levels of 10-bit memory mapping fields and 12-bit offset within page, 32-bit Windows should be able to map maximum 210+10+12 byte = 4GB? Then why 16TB?