Portland, Oregon is 13% larger than Kansas City, Kansas.
Area: 332 km2 calculated
Kansas City is the third-largest city in the state of Kansas, the county seat of Wyandotte County, and the third-largest city of the Kansas City metropolitan area. It is part of a consolidated city-county government known as the "Unified Government". Wikipedia
Area: 376 km2 calculated
Portland is the largest city by population in the U.S. state of Oregon, near the confluence of the Willamette and Columbia rivers. Wikipedia