Summit, the US's new supercomputer, is more than twice as powerful as the current world leader.
The machine can process 200,000 trillion calculations per second - or 200 petaflops.
China's Sunway TaihuLight supercomputer, until now the world's most powerful machine, has a processing power of 93 petaflops, reports BBC.
Summit's initial uses will include areas of astrophysics, cancer research and systems biology.
It is housed at Oak Ridge National Laboratory (ORNL) in Tennessee, where it was developed in partnership with IBM and NVidia.
Supercomputers are typically large, expensive systems featuring tens of thousands of processors designed to carry out specialised calculation-intensive tasks.
Summit contains 4,608 compute servers and has more than 10 petabytes of memory.
ORNL director Dr Thomas Zacharia said in a speech to mark its launch on 8 June that Summit had already been used to run a comparative genomics code while it was being built.
"Literally as the machine was being assembled they were getting on the machine and running," he said.
"Imagine [driving a] race car while you're putting the tyres on."
