I know that Japan has loosened restrictions, but I just returned from a short trip and 95% of the people in Tokyo still wore marks, especially in smaller spaces like trains. Those who didn’t wear masks were looked at as loud, obnoxious people and/or anti-vaccine people. You may get a free pass as a foreigner, but if you’re Asian that doesn’t apply either. There are also places that require you to wear masks; I attended a concert that did so, and a few restaurants asked that I keep my mask on when not eating. This will eventually go away, but as of right now (3/21/2023), I recommend you still carry a mask with you just in case. Also, if you’re going in the spring, a mask really helps with allergies anyway.
As for what mask to use? Any non-woven mask mask will work, so surgical masks are fine. Cloth ones are fine also for the most part, though some places require non-woven masks. This Amazon search should show you what masks are common. You can also simply purchase a pack at any convenience store or drug store in relatively small amounts.
Good news! The Japanese government has now downgraded the severity of COVID to that of the common flu and as such you no longer need to wear a mask during your trip:
Even at the height of the pandemic, mask wearing was never a legally
required mandate here in Japan. Nevertheless, it has become a common
practice in the country.However, Japan has decided to reclassify Covid-19 as just a seasonal
flu on May 8. In line with that, the government is also looking at
relaxing the rules of mask-wearing. According to NHK, you can soon
decide whether to wear a mask indoors, and this takes effect on March
13.
Just look at some recent "walking tours" in Japan (example). Most people simply wear a surgical mask.
A few wear nothing or use masks as chin diapers.
Credit:stackoverflow.com‘