4 g/kg to PSU

4 g/kg = 4.02 PSU

g/kgPSU
2.5 g/kg2.512
3 g/kg3.015
3.5 g/kg3.517
44.02
4.5 g/kg4.522
5 g/kg5.024
5.5 g/kg5.527

4 g/kg = 4.02 PSU

Formula

1 g/kg ≈ 1.0049 PSU · 1 mg/L ≈ 0.001 PSU · 1 ppm ≈ 0.001 PSU (dilute aqueous approximation)