I've always thought that surface area of shelving for the refrigerator and door would be truer. I've never read that anywhere, but there's not a lot that gets stacked (optimally) in a fridge. In a freezer, at least for me, stuff does get stacked. I can't think of a good measure for that. I think cubic feet is as good as anything.

CR lists usable space in their reviews.

Shelf space is more important than cubic feet. You can fit more in a 33" wide French door fridge than a 36" SxS. The consumer grade fridges with the most usable capacity are the LG, Samsung, and GE 29 cu ft French door fridges. If that's not enough for you, then it's time to cut the cord to the freezer and put in an all fridge, with a separate freezer elsewhere.

Shelf space doesn't always tell the story either since some things can stack and others can't. If you can go look in a store, take a bunch of clean empty bottles and cans and containers, some plates and bowls without lids, and some of your kid's (or dog's) plush and/or squeeky toys (washed) to simulate things like tomatoes. Try loading up a fridge you're interested in and see how stuff actually fits. Like the door rack that looks like it should hold three pop bottles, but because of the shape of the butter box, really doesn't. :)

Heed Pllog's advice before you buy!

Also, as weed notes, CR calculates actual usuable space for each fridge that they test plus other models that seem very similar to the tested ones. So does www.refrigeratorinfo.com. They do what cal_quail suggested -- measure the shelf space and then compute the storage volume of the space above that shelf on up to the next shelf.

Although both sites use very similar tests, CR could take lessons from the refrigeratorinfo's presentations of the details of the results. However, refrigeratorinfo tests far fewer fridges than it lists, so there may not be info on models you happen to be interested in. Also, dial up your browser's your pop-up blocker to high because the site is sometimes rife with adverts.

This post was edited by JWVideo on Mon, Jul 7, 14 at 19:44

This is a tough question. We did a test that shows numbers provided by manufactures are to say the least deceiving.

We filled a Liebherr 30" wide (80" high) refrigerator and a standard KitchenAid 36" (72" high) wide refrigerators with bottles of water you buy in a 24 pack in the store. See results below.

Manufacturers Specs on capacity

Liebherr Ref 11.3 cu ft
Liebherr Fre 4.2 cu ft
TOTAL 15.5 cu ft

KitchenAid Ref 14.4 cu ft
KitchenAid Fre 5.4 cu ft
TOTAL 19.8 cu ft

Liebherr Ref 264 bottles
Liebherr fre 73 bottle
Total 337

KitchenAid Ref 222 Bottles
KitchenAId fre 57 Bottles
Total 279

So the question is how can a Liebherr hold 58 bottles (OVER TWO CRATES) more than a kitchenaid that has about 25% more capacity ? Answer..... the layout inside a liebherr is very simple with no fancy rounded off drawers no ice maker taking up space and better shelve and door layout.

The only thing you can do as a consumer is to open the doors and visualize what you would put in the refrigerator and where.