How many mls in 12 ounces?

Answer 1

12 ounces of what?

mls are a measure of volume, ounces are a measure of weight.

12 ounces of Mercury is a lot smaller in volume than 12 ounces of hydrogen.

If you mean fluid ounces (which are a measure of volume):

1 fl oz = 0.028413 litres

12 fl oz = 12 x 0.028413 litres = 0.340956 litres ~= 341ml

1 fl oz = 0.029573 liters

12 fl oz = 12 x 0.029573 liters = 0.354876 liters ~= 355ml