The box size of unit cell is in gromacs tutorial command line

GROMACS version: 5.1.1

I have an enquiry about the box size of unit cell is in the gromacs tutorial command line i.e
gmx editconf -f complex.gro -o newbox.gro -bt dodecahedron -d 1.0, it is in angstrom or nanometer

Hello!

It is in nanometers.