@egirlyuumimain @VD15 All of those units are defined based off a metric unit - so using those units is using metric with extra steps - you should just use metric directly.

See GNU units output;
You have: pint
You want:
Definition: 1|2 quart = 0.00047317647 m^3
You have: quart
You want:
Definition: 1|4 gallon = 0.00094635295 m^3
You have: cup
You want:
Definition: uscup = 8 usfloz = 0.00023658824 m^3
You have: teaspoon
You want:
Definition: usteaspoon = 1|3 ustablespoon = 4.9289216e-06 m^3
You have: tablespoon
You want:
Definition: ustablespoon = 1|16 uscup = 1.4786765e-05 m^3