The fair place to meet is Raleigh-Durham, NC — the city closest to the midpoint of Boston and Miami. From the farther side that’s about 14 hr 38 min of driving.
Recommended midpoint
Raleigh-Durham, NC
From Boston
12 hr 47 min
609 mi to Raleigh
From Miami
14 hr 38 min
698 mi to Raleigh
Boston has the shorter trip; the split is off by about 1 hr 51 min. The alternatives below can even it out. Boston and Miami are about 1,258 miles apart.
Boston and Miami are about 1,258 miles apart by road. Split the difference and you arrive near Raleigh, the city closest to the halfway point between them. That puts roughly 12 hr 47 min of driving on the Boston side and 14 hr 38 min on the Miami 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. Raleigh still makes a fair, central place for Boston and Miami to converge, splitting the travel instead of asking one side to cross the country.
If Raleigh doesn't have what you're after, Richmond and Charlotte are also close to the midpoint and worth a look — each keeps the drive reasonably balanced between Boston and Miami.
Raleigh is the capital city of the U.S. state of North Carolina. It is the second-most populous city in the state, tenth most populous city in the Southeast, the largest city in the Research Triangle area, and the 39th-most populous city in the U.S. Read more →
Boston is the capital and most populous city of the U.S. state of Massachusetts. It serves as a cultural and financial center of New England, a region of the Northeastern United States. Read more →
Miami is a coastal city in the U.S. state of Florida. It is the second-most populous city proper in Florida, with a population of 442,241 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.