thinking of buying the japan national rail pass for 21 days

Hi there,

For a 21 day rail pass to be cost effective you need to spend over ¥57,700 on individual JR tickets. I think based on your listed travel it is unlikely you'll spend that without doing more long distance travel, but lets take a look at your costs:

1. Kansai airport > Osaka: ¥2600, (53mins, 57km)
2. Osaka > Kyoto: ¥540, (29mins, 42km)
3. Kyoto > Osaka: ¥540, (28mins, 42km)
4. Osaka > Kyoto: ¥540, (29mins, 42km)
5. Kyoto > Nagoya: ¥5640, (49mins, 147km)
6. Nagoya > Tokyo: ¥10780, (106mins, 366km)
7. Tokyo > Odawara: ¥3840, (35mins, 83km)
8. Odawara > Tokyo: ¥1450, (36mins, 83km)
9. Tokyo > Maihama: ¥210, (15mins, 12km)
10. Maihama > Tokyo: ¥210, (16mins, 12km)
11. Tokyo > Kansai airport: ¥15000, (266mins, 613km)

TOTAL: ¥41350 for 11 legs

• Please note that I have assumed you'll visit Nagoya in Aichi and return to Osaka to fly back home.

As you can see, the total legs for your trip do come under the 21 day pass total, so I don't think I'd recommend a 21 day pass for you unless you do another ¥16,350 of JR travel.

I may recommend a 7day pass if you think you'll return from Kyoto to Tokyo within a 7 day period. The Tokyo to Kyoto return on the bullet train costs around the same as a 7 day pass (¥28,300), and so it would be worth purchasing a pass in these circumstances.

Hope this helps!