If you're like me and like making your own whipped cream, you might be a little overwhelmed at the grocery store when you're looking for heavy （or regular) whipping cream. You want to look for 生クリーム, and you'll find the creams in the milk section most likely, usually in very small (200ml / less than 1 cup) packages. They'll look something like this:
Now cream is differentiated by fat content. In the U.S., regular whipping cream is usually in the 30-35% range. Heavy whipping cream is 36% fat or higher. This cream here is 47% fat, and whips very very nicely. But they also have heavy cream in the more normal 36-40% fat range. (Interestingly, 47% cream is considered manufacturers cream in the US and is not usually available in grocery stores but used in professional settings. Its very close to the British double cream, which is 48% fat.) I should add that creams with more fat in them whip up better and are more stable when whipped.
In any case, this particular brand has the fat content right in the title, 純生クリーム４７. But if your cream doesn't have that in the name, you want to check the ingredient list.
The characters read 乳脂肪分, which means butterfat amount.
As I said before, most ingredients in Japan are expensive. At my supermarket in Azabujuban in Tokyo, which is known for high prices, this ran about ￥130 (or about $1.30 with today's exchange rate). Not bad, but keep in mind this is a very small amount of cream. Good enough for adding cream to something, but not enough to ice a cake with whip cream instead of frosting. I've found bigger cartons (800-1000 ml?) of whipping cream at higher end grocery stores, but those were about ￥1100-1200. Pricey compared to the U.S.
On a fun note, perhaps because its Christmas time, this particular whipping cream came with a nice surprise. If you look at the first two pictures, you'll see a funny tube attached to the cream. I opened it up and its actually an icing bag, icing tip, and instructions for usage and for making whipped cream. What a nice addition! :)
And just for fun, here's my version of a Japanese Christmas Cake, made for a child's Christmas party.
If you like the design you can find instructions at http://www.keyingredient.com/recipes/742875032/strawberry-santa-cake/