It’s a little tricky to wrap your head around the prices in Japan. Most things are more expensive in than in the US, but it depends on what you buy. Pizza, for example, is far more expensive and you’ll probably get quite a shock after ordering your first pizza here. The amount of pizza that you get per dollar/yen is far less than you’d expect.
Check out this great video from the alivenotdead blog, which nicely illustrates what kind of pizza you can expect to get for about 3000 yen in Japan. This is pretty tiny!