The flight distance from Netaji Subhash Chandra Bose International Airport (CCU) in Kolkata, India to Boulder Municipal Airport (WBU) in Boulder, United States is 12,901 kilometers (8,017 miles / 6,966 nautical miles). The estimated flight time for this route is approximately 16h, flying north northeast at a heading of 12°.

This is an ultra-long-haul route, one of the longest in aviation. It requires wide-body aircraft with extended range capability such as the Airbus A350-900ULR or Boeing 777-200LR. Passengers should prepare for an extended flight with multiple meal services.

This is an international route connecting India with United States. It is an intercontinental flight between Asia and North America. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 23:07 in Kolkata, it's 10:37 in Boulder. With a 12.5-hour time difference, travelers should plan for significant jet lag. It typically takes one day per hour of time difference to fully adjust.

There is a significant elevation difference of 5,272 feet between the two airports. Boulder Municipal Airport sits higher than Netaji Subhash Chandra Bose International Airport. Travelers arriving at the higher-elevation airport should be aware of potential altitude effects.

The return flight from Boulder (WBU) to Kolkata (CCU) follows a heading of 346° (north northwest). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the Netaji Subhash Chandra Bose International Airport (CCU) and Boulder Municipal Airport (WBU) detail pages, or use our flight duration calculator to compare other routes.