Are there nonstop flights from Osaka (KIX) to Kolkata (CCU)?

No. The fastest connection is via Shanghai, about 6h 34m of total flying time.

What is the fastest connection from Osaka (KIX) to Kolkata (CCU)?

via Shanghai ≈ 6h 34m, via Guangzhou ≈ 6h 52m, via Hanoi ≈ 6h 55m (estimated flying time, excluding layovers).

from 19,000 ANA miles, from 37,000 JAL miles (economy, one way, based on the published award charts).

Kansai International Airport (KIX) to Netaji Subhash Chandra Bose International Airport (CCU)・4,711 km

No nonstop flights. The fastest connection is via Shanghai (PVG), about 6h 34m of flying time (layover not included).

With milesANA 19,000 miles+ (via BKK)JAL 37,000 miles+ (via KUL)Economy, one way, estimate. Tap a connection for miles by cabin.

None.

8 one-stop options, sorted by estimated flying time. Tap one to see the airlines on each leg and booking links.

Times are estimated from distance. Check schedules, frequency and availability with the airline or a booking site.