The fair place to meet is Oklahoma City, OK — the city closest to the midpoint of Columbus and Phoenix. From the farther side that’s about 17 hr 50 min of driving.
Recommended midpoint
Oklahoma City, OK
From Columbus
17 hr 50 min
851 mi to Oklahoma City
From Phoenix
17 hr 37 min
840 mi to Oklahoma City
That’s an even split — both sides drive within 13 min of each other. Columbus and Phoenix are about 1,664 miles apart.
Columbus and Phoenix are about 1,664 miles apart by road. Split the difference and you arrive near Oklahoma City, the city closest to the halfway point between them. That splits the trip almost evenly — about 17 hr 50 min from Columbus and 17 hr 37 min from Phoenix.
Over this distance most people will fly rather than drive the whole way. Oklahoma City still makes a fair, central place for Columbus and Phoenix to converge, splitting the travel instead of asking one side to cross the country.
If Oklahoma City doesn't have what you're after, Kansas City and Dallas are also close to the midpoint and worth a look — each keeps the drive reasonably balanced between Columbus and Phoenix.
Oklahoma City, often shortened to OKC, is the capital and most populous city in the U.S. state of Oklahoma. It is the 21st-most populous U.S. city and 8th largest in the Southern United States, with a population of 681,054 at the 2020 census. Read more →
Columbus is the capital and most populous city of the U.S. state of Ohio. With a population of 905,748 at the 2020 census, it is the 14th-most populous city in the U.S., second-most populous city in the Midwest, and third-most populous U.S. state capital. Read more →
Phoenix is the capital and most populous city of the U.S. state of Arizona. With over 1.6 million residents at the 2020 census, Phoenix is the fifth-most populous city in the United States and the most populous state capital. Read more →
City descriptions adapted from Wikipedia (CC BY-SA); photos via Wikimedia Commons, credited above.
Estimates use straight-line distance and typical road speeds; real drive times vary with route and traffic.