Would you recommand 14 or 21 days JR Pass?

Arrive to Narita AirPort the 24/3-2017
Stay in Tokyo from 24/3-31/3 8 days)

From Tokyo to Kyoto the 31/3 (7 days) until 7/4

From Kyoto we haven't decided where to go? We are flying back home from Narita AirPort the 12/4, but I Think we are going to visit Nara/Osaka, Toyosato(Shiga), mt. Fuji, but we wil NOT decide if we want to go to Hiroshima or back to Tokyo for the last 6 days? But I Think we will return to Tokyo for at least 1-2 days?

Thanks

Check your itinerary.

Mt. Fuji can be a day trip from Tokyo if you want to.

Compare roundtrip shinkansen tickets from Tokyo-Kyoto plus any Kansai regional pass and your other travels in JR lines against 14- or 21-day JR Pass.

I wouldn't recommend either JR pass. You're spending too much time in one place (not that that's a bad thing!) to make a pass worth it.

Agreed. With the current plan. No need for JR nation wide passes.

But the vagueness of the itinerary doesn't help anyone deliver a good helpful suggest or advice.

Figure out where you wanna go and what you wanna do, then make a decision on transport.

Normally if you do a trip from Tokyo to Kyoto and Hiroshima, a 7 day pass will pay off. So plan you Itinerary with a 7 day block including Kyoto and Hiroshima.