Home use, max 25000 BTU per burner,
Max BTU is measured by the single burner that has the max output of all burners on a gas stove top. For a 25000 BTU burner, it must be an open burner, which is professional but hard to clean. Those stove tops are every expensive, usually cost more than $5000.
For home use and easy to clean, it is better to buy a stove top with sealed burners, which can be max 18000 BTU and cost much less.
For home use gas stove tops, Dacor is a very good brand making sealed burners.