Well I have developed an excel file that converts the grams that soapcalc shows for a recipe (oils-water-NaOH), to total ml.
I've used an average value of 1.09 for the specific weight of oils (values range from 1.09 to 1.1 among various oils) and calculate the liquid form of NaOH that has a volume a little more than its half weight when being in anhydrous form.
It also calculates the total metric capacity of a rectangular and cylindrical mold (ml), while it also shows the vertical height that the soap loaf will have in these molds with the specific recipe.
It seems to be working for me quite well.
https://www.dropbox.com/s/6ckxe5fte791ufd/CalculateMold-cm2ml_en.xls?dl=0
ETA:
If I'm calculating something wrong please correct me
Uh, what?