A National Leader
The Livermore Computing Complex powers LLNL’s national security mission with advanced computing, simulation, AI, and data capabilities that also enable breakthrough science. Anchored by El Capitan, the National Nuclear Security Administration’s first exascale supercomputer, and Tuolumne, LLNL’s unclassified Advanced Technology System, the complex supports more than 3,000 scientists and engineers solving mission-critical challenges at scale.
LLNL designs, deploys, and operates a broad range of advanced computing systems to support mission-driven science, engineering, and national security work. Our portfolio includes production Linux clusters, AI accelerator platforms, and specialized testbeds for evaluating emerging technologies, supporting workloads from modeling and simulation to data-intensive analytics and machine learning. This breadth of infrastructure enables LLNL to assess new capabilities, deliver robust production services, and provide a flexible foundation for innovation across diverse research and operational needs. With advanced infrastructure, powerful hardware and software, and deep technical expertise, LLNL provides the computing environment needed to strengthen national security, accelerate scientific discovery, and push the frontiers of technology.
Facility Spotlight
Computing and simulation operations are conducted in remotely monitored and controlled computer rooms located across the LLNL site. The largest facility—48,000 square feet—offers over one acre of floor space for computing with 37.5 MW power for systems and peripherals and additional power for machine cooling. Engineering and facilities staff maintain this LEED-certified facility alongside operations staff working 24 hours a day, seven days a week.
El Capitan
El Capitan arrived in 2024 and is now delivering over 2.8 peak exaflops of computing power to support advanced simulations for nuclear deterrence, weapon modernization, material science, advanced manufacturing optimization, and other national security and scientific missions. As the Laboratory’s flagship classified supercomputer, it provides researchers with world-class high performance computing capabilities to tackle some of the most complex and consequential problems in science and security. El Capitan is designed to enable next-generation modeling, simulation, and data analysis at unprecedented scale, helping advance discovery, strengthen national security, and support the Lab’s mission priorities.
Tuolumne
Tuolumne is one of El Capitan’s unclassified companion systems, built on the same architecture at a smaller scale. With nearly 300 petaflops of peak performance, it enables lab researchers and our collaborators access to the world-class HPC capabilities needed to strengthen national security, accelerate scientific discovery, and drive advances in science and technology. Tuolumne supports a wide range of unclassified research, including computational biology, energy security, earth science systems, astrophysics, and disease therapeutics.
The Most Computing Power in the U.S.
LLNL Computing Power in Petaflops (1015 floating-point operations per second):
