It's not easy to answer. Japan has a packed festival and event calendar: many of them are worth a visit.
Japan has a beautiful cherry blossom season in Spring, passionate Summer festivals, Autumn colors, excellent skiing and Winter festivals. It's really up to the individual traveler's tastes.
Yeah, but when is best?The first week of April is an excellent time to visit Japan. Sakura are almost guaranteed to be in bloom in both Tokyo and Kyoto. It's everyone's favorite time in Japan. There are big parties under the cherry trees. The smell of Spring is in the air.
Best of all, April 1st is the beginning of a new company and school year in Japan. Prices for travel within Japan aren't too bad at this time.
When is worst?Prices for travel in Japan skyrocket whenever there is a big holiday. The most expensive times are:
New Years (December 31st - January 5th)
Golden Week (end of April - start of May)
Obon (mid-July and mid-August)
It's also best to avoid the Japanese rainy season.
The season varies by location and year. For the approximate dates, check our Japan Event Calendar. There's also a month by month description of Tokyo weather here.