Ice Cream Butterfat Calculator
Double Cream (48%): cups or: fl. oz or: ml
Heavy Whipping Cream (37%): cups or: fl. oz or: ml
Light Whipping Cream (30.9%): cups or: fl. oz or: ml
Light Cream (19.3%): cups or: fl. oz or: ml
Half-and-half (11.5%): cups or: fl. oz or: ml
Sweetened Condensed Milk (8.7%): cups or: fl. oz or: ml
Evaporated Milk (7.6%): cups or: fl. oz or: ml
Whole Milk (3.25%): cups or: fl. oz or: ml
2% Milk (2%): cups or: fl. oz or: ml
Skim Milk Powder (0.8%): cups or: oz (weight) or: g
Skim Milk (0.2%): cups or: fl. oz or: ml
Soy Milk (Silk brand) (1.7%): cups or: fl. oz or: ml
Soy Milk Creamer (Silk brand) (6.7%): cups or: fl. oz or: ml
Coconut Milk (21.3%): cups or: fl. oz or: ml
Butter (81.1%): cups or: oz (weight) or: g
Cream Cheese (79.8%): cups or: oz (weight) or: g
Sugar: cups or: oz (weight) or: g
Honey: cups or: oz (weight) or: g
Cocoa powder: cups or: oz (weight) or: g
Chocolate (melted squares): oz (weight) or: g
Eggs: Jumbo    Ex Lg    Lg    Med    Small
Egg yolks: Jumbo    Ex Lg    Lg    Med    Small
Total butterfat by weight: 0.0%
Total fat by weight: 0.0%
Total NFMS by weight: 0.0%
Total sugar by weight: 0.0%
Total weight: 0g

Total butterfat by weight is the fat from just the milk and cream.

Total fat by weight is the percentage of normal "lipid" fat, which includes the butterfat and the fat from things like eggs and chocolate as well.

Nonfat Milk Solids, or NFMS as they refer to it in the commercial ice cream business, is basically the "solid" part of skim milk. NFMS doesn't play a big part in making homemade ice cream, but it does in making commercial ice cream, where they add some amount of dry milk powder depending on the amount of butterfat in the recipe. The less butterfat you use, the more NFMS you use to make up for it.

More info can be found in my blog post Making an Ice Cream Butterfat Calculator.

I have no idea if this is actually accurate. ;-)