There are two main international airports into Japan, Tokyo Narita and Osaka  Kansai.

Arriving via Narita is a little quicker than Osaka. Average fly time around the world into Narita:

Asian Region

• Hong Kong: 3hrs 45mins (Time diff + 1hr)
  
• Singapore: 6hrs 30mins (Time diff +1hr)
• Seoul: 1hr 30mins (Time diff 0hr)
• Shanghai: 2hrs 15mins (Time diff +1hr)
• Beijing: 2hrs 45mins (Time diff +1hr)

Australia

• Sydney: 9 hrs 45mins (Time diff - 1hr)
• Brisbane: 9hrs 30mins (Time diff -1hr)
  
• Gold Coast: 9 hrs 30mins (Time diff -1hr)
  
• Melbourne:12hrs 30mins, via Sydney (Time diff -1hr)
  
• Adelaide: 14hrs, via Sydney (Time diff +30mins)
  
• Perth: 10hrs (Time diff +1hr)

New Zealand

• Auckland: 11hrs (Time diff -3hrs)
• Wellington: 13 hrs (Time diff - 3hrs)

Europe

• London: 11hrs 30mins(Time diff +8hrs)
  
• Paris: 12hrs 30mins (Time diff +7hrs)
• Frankfurt: 11hrs (iIme diff +7hrs)

America

• Los Angeles: 12hrs (Time diff +18hrs)
  
• San Francisco: 11hrs 20mins (Time diff +18hrs)
• New York :14hrs (Time diff +13hrs)