I live in the U.S. and will be traveling to Japan. Will my electric plugs work there?

yes, the us and japan have the same voltage and outlet size, you have nothing to worry about

Yes..In Japan also they are using 110 V.

Plug type is also same as of USA>

They are not useing the same voltage, but the difference is so small that yes you can use your appliances there, and the shape is the same.

Its the same type of plug.
The wattage is slightly weaker. But everything works fine.

For the most part, yes. Most electronics will work fine. However, there are almost no three-prong plugs in Japan, so if you have something that requires a three-prong (grounded) outlet, then you will need an adapter of some kind. And if you're staying in a hotel, most hotels only have one, maybe two available plugs in a room.