The fair place to meet is Indianapolis, IN — the city closest to the midpoint of Detroit and Oklahoma City. From the farther side that’s about 14 hr 26 min of driving.
Recommended midpoint
Indianapolis, IN
From Detroit
5 hr 2 min
240 mi to Indianapolis
From Oklahoma City
14 hr 26 min
688 mi to Indianapolis
Detroit has the shorter trip; the split is off by about 9 hr 24 min. The alternatives below can even it out. Detroit and Oklahoma City are about 909 miles apart.
Detroit and Oklahoma City are about 909 miles apart by road. Split the difference and you arrive near Indianapolis, the city closest to the halfway point between them. That puts roughly 5 hr 2 min of driving on the Detroit side and 14 hr 26 min on the Oklahoma City side — the fairest single meeting point among the cities near the middle.
Over this distance most people will fly rather than drive the whole way. Indianapolis still makes a fair, central place for Detroit and Oklahoma City to converge, splitting the travel instead of asking one side to cross the country.
If Indianapolis doesn't have what you're after, Kansas City and Louisville are also close to the midpoint and worth a look — each keeps the drive reasonably balanced between Detroit and Oklahoma City.
Indianapolis, colloquially known as Indy, is the capital and most populous city of the U.S. state of Indiana and the county seat of Marion County. Indianapolis is situated in the state's central till plain region along the west fork of the White River. Read more →
Detroit is the most populous city in the U.S. state of Michigan. It is situated on the bank of the Detroit River across from the Canadian city of Windsor, Ontario. It is the 26th-most populous city in the United States and the largest U.S. Read more →
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 →
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.